Ok. So, let's say you had bought several little house plans (the big enchilada and the 20x30) and then decided to build something else, and kind of somehow without any plans (explaining how is too painful) ended up with a crawlspace poured, and 8"x8"x16" concrete walls all built up, and it's all surface bonded. Looks good to me so far considering its me doing it.
How in the world do I get a roof on this bad boy? The dimensions are 38'x34', with the roof line running parallel to the 34' walls (slopes down toward the 34' walls).
I wasn't really that worried about it because I had so much other stuff to do before that became an issue, but the time has come. A few more bags of surface bonding are all that remains.
I haven't put my suspended wood floor in because everything takes me so long I figured it would get all moldy and nasty if I didn't put the roof on first, and then I guess just stick frame in the interior walls.
So I asked my brother who is a building supervisor for a home building company "hey can you just tell me who your framing guys are and I can pay them to put a roof on my house for me rather than me trying to make it happen" and he made it sound like no one would touch it because I have no plans.
So....any ideas? I'm ready to do this next stage but am a little lost. How do I go from "concrete wall box" to "concrete wall box with roof."
So my wife contacted this guy who makes trusses and he said they would cost about $2400 dollars for that span and that size of house. That would be cool, but do I need my interior walls in first so they can help hold the trusses up or do they just span all the way all by themselves? I was hoping to do the roof then the floor and interior walls even if its more of a pain that way.
The truss guys probably assumed they would have to span the entire building. Easy enough to call and verify. You'll need a crane to set those rascals.
You didn't give any info about roof pitch, wind or snow loading, or if you are in an earthquake or hurricane area. All things the local truss guy would know as well. If you had all the parameters you could figure what the rafters would be, but given the span they will be large in any case.
I counted 17 courses of block. Is there a poured tie beam up there? Anywhere I've been would require one after 16 courses. If you don't have a tie beam try to design a roof that doesn't put a lot of outward force on those walls.
Just my opinion and as always YMMV. Might not be a bad idea to bounce it off an engineer.
I think John C covered it - trusses usually span the whole thing and don't even want interior supports - interior walls are non-bearing. As he said - verify with the truss co - they engineer the trusses but the walls are on you. :)
Hi Guys,
Thanks for your responses!
No there is no tie beam. Don't trusses by their nature only exert downward force on the walls because of the cross tie thingys? I assumed that just from looking at the way they are designed. I guess I could do some kind of tie beam, I just got sick of crawling up a ladder with 2 gallon buckets of concrete so I figured that with my Uber Foundation and that its tied into bedrock limestone with rebar that it wouldn't move much from that angle and that the trusses wouldn't cause a enough separating force on the walls. Maybe I should do that while I still have a chance... hm...
I thought "eh, I'm going to mortar bolts into the top row and bolt some kind of big pressure treated board thing to it to give me something to nail the trusses to, so won't that kind of hold it together?"
What is YMMV?
Thanks for the info on the no-load-bearing walls. I told me wife that and then she said she remembered him saying that it doesn't need any load bearing walls but that was the first time I had heard that information!
Regarding the slope and snow load, I figured the truss engineer guy would just say "here's what you need". I live in the Texas hill country so while we had tons of ice this year usually there isn't any snow or ice and things like that.
Thanks guys!
In theory, under normal conditions the trusses only exert downward forces. The 38' wall is a 430 sq ft sail/billboard; plus the area of the roof itself and the gable ends. High winds can put a lot of pressure on that area.
Block walls are quite strong in compression, but not particularly strong in other ways. Different codes deal with it by requiring a tie beam and/or vertical columns. I would poke around and see what has been done in the area. It may be quite normal for your neck of the woods.
There are a lot of folks here with much more concrete experience than I have, maybe they will chime in as well.
Yes, trusses should span the entire 34' width and you can specify the pitch. They will be designed for your local loads. You do need something solid to anchor the trusses to - like a PT sill plate with anchor bolts into the concrete (you have that detail in the Enchilada set of plans).
Interior walls can go in later. But, I'm not clear about what is happening with the floor. Have you cast bolts into the wall for a PT ledger to carry a joist floor system? Is the crawlspace vented? Sealed and insulated?
John C has mentioned the issue of racking resistance (wind and earthquake sidewards loads) on the block walls. Surface bonded walls can help with this issue but don't usually eliminate the need for steel, especially in such a long unsupported wall. In the old days, before steel reinforcing, master builders would drop in massive pylons - basically heavy stone or concrete posts to anchor thinner walls at perhaps 12' intervals.
If needed after the fact, you could always consider a flying buttress ;)
YMMV - your mileage may vary-- meaning --could be different under your circumstances.
A bond beam is a solid poured beam that ties all of those loose blocks together in case of accident or if someone like me were to accidentally bump them while putting up the trusses. I once bumped a stack of mortared blocks and knocked down about 40 of them.
While surface bonding is great for fast stacking it looks like from this site that solid poured columns and bond beams are still necessary for earthquake bracing. http://www.drystacked.com/sequence.html
http://www.drystacked.com/windows.html Shows headers and bond beam with double rebar on top. The bond beam would give you a place to put your anchor bolts also to tie the roof trusses on or bolt a wood plate to.
(//%3Cbr%20/%3Ehttp://www.drystacked.com/album/images/91160263_JPG.jpg)
If you are totally open to the bottom you could put rebar in and solid grout columns into the hollow cells every so often for posts, then bend and lap the rebar into the beam at the top.
QuoteYes, trusses should span the entire 34' width and you can specify the pitch. They will be designed for your local loads. You do need something solid to anchor the trusses to - like a PT sill plate with anchor bolts into the concrete (you have that detail in the Enchilada set of plans).
Interior walls can go in later. But, I'm not clear about what is happening with the floor. Have you cast bolts into the wall for a PT ledger to carry a joist floor system? Is the crawlspace vented? Sealed and insulated?
John C has mentioned the issue of racking resistance (wind and earthquake sidewards loads) on the block walls. Surface bonded walls can help with this issue but don't usually eliminate the need for steel, especially in such a long unsupported wall. In the old days, before steel reinforcing, master builders would drop in massive pylons - basically heavy stone or concrete posts to anchor thinner walls at perhaps 12' intervals.
If needed after the fact, you could always consider a flying buttress ;)
Hm...I have a massive beam going down the middle that is 3 2X12's thick bolted/glued together that I was going to put ~17' 2X12's on as a floor joist system. As far as how to attach to the wall, it will attach to the second row of blocks. I was going to get Pressure Treated board and screw it around the perimeter. I filled every few with concrete up to this level so I was going to screw into it with gozillions of big concrete anchor screws, the kind you have to predrill for. Then I was going to I guess nail the floor joists into that. Then maybe use some construction adhesive to put some little 2x4 supports underneath the board that goes around the perimeter that the joists attach to, and use that to give some more support underneath.
As far as sealed and insulated, all I have is a big beam going across. In the middle is dirt, weeds, trees... you get the idea.It's in the raw as of now. I was just going to do the joists/decking thing after it would all be protected from the roof being in place.
As far as venting, I just turned some blocks on their sides at the floor level to provide some holes for ventilation. i thought i could just attach some screen to it to keep rodents out. I was also going to put a fan on them to help pull air through.
I also intend to put down some black plastic before i put the floor in, to keep moisture out.
I attached a picture of the project from quite a bit earlier, but it shows how the inside is right now. Lots of grass, fuzzy forest creatures, and a big beam waiting to have joists attached to it...one day.
I'll have to give some thought to the bond beam. my first thought is, the walls were up for almost a year and this winter endured the worst weather i have ever seen in this part of Texas in the last 15 years, and they were only half surface bonded. Wind, tornadoes near by, ice, snow, hail, thunderstorms, the works. I think I would rather do vertical columns with rebar every five or six holes (or whichever holes i can see clear to the bottom) than do a bond beam. Also a bond beam would add undesired height to an already kind of too-tall wall at this point. I know i know I probably should have done one before I got that high. Also I put on surface bonding uber thick. If I had to pick I would do vertical columns before I did a bond beam.
Definitely don't want to try flying buttresses, that is a LOT of stonework and I don't have one single vassal much less the multitude of vassals it would take to complete such a job in a timely manner! haha
QuoteYMMV - your mileage may vary-- meaning --could be different under your circumstances.
A bond beam is a solid poured beam that ties all of those loose blocks together in case of accident or if someone like me were to accidentally bump them while putting up the trusses. I once bumped a stack of mortared blocks and knocked down about 40 of them.
While surface bonding is great for fast stacking it looks like from this site that solid poured columns and bond beams are still necessary for earthquake bracing. http://www.drystacked.com/sequence.html
http://www.drystacked.com/windows.html Shows headers and bond beam with double rebar on top. The bond beam would give you a place to put your anchor bolts also to tie the roof trusses on or bolt a wood plate to.
(//%3Cbr%20/%3Ehttp://www.drystacked.com/album/images/91160263_JPG.jpg)
Hm..If it is just for earthquake bracing i think I'll take my chances with the earthquake on the bond beam thing. I don't think we have earthquakes in this area as far as I am aware. I'm not sure I have the emotional fortitude to go back and do a bond beam! I've been living in an RV for five months and am going to cry if I don't get a roof on this building soon! Also, I have lots of doors and windows (not on that one wall I sent a picture of, but on the rest of the house) and they have like kind of bond beams where the lintels span across multiple doors and windows, just a few blocks below top level, and it has tons of rebar. My french door even has 1" rebar going all the way across the lintel poured in concrete, tied down the sides poured with concrete and into the foundation which is tied into bedrock with rebar. Most of my doors are done this way, except the other doors have 1/2" rebar across the top instead of the 1" i used in the french door lintel.
I probably will go with vertical columns every few holes. My brother has a bunch of rebar that he lets me use some of it, so I can do that without having to add more height to the wall which is already kind of too high I think.
As far as anchoring roof to the top, I guess I will put bolts into the holes in which I will have done vertical rebar/concrete and try to tie it in that way.
Here's a pic of the kids helping out.
Work in progress.
The vertical columns cemented wouldn't do much without the bond beam. Some but not much in case of earth quake. Maybe you don't have that problem down there - Unless you are in an area of subsidence because of oil pumping - that could break it up eventually. The bond beam could be put in by cutting about 1/2 or 2/3 the way down the blocks in the center and taking it ou with a hammer but I don't know about stopping the holes. A plumber I knew used to wad up news paper and jamb it in the hole then pour some flowable grout for plugging 4" waste lines. I think I have see them put a row of 30 lb felt or something to keep the concrete from going to the bottom but most jobs I am on are filled solid. I guess you could put felt in the channel made by breaking the centers out. Doesn't matter to me -- just throwing out ideas in case you want to use them.
Also I see you have a footing inside the wall - could you just put a pt plate and or blocking there to support the ends of your floor joists?
If you do the columns and put bolts you could bolt a wood beam there to set your trusses on. That would tie most of it together after a fashion. Might even have room to splice the ends of the wood beam together decently. :)
Looks like a willing crew -- just a tad on the short side. Looks like they are learning anyway. :)
Here is an idea
Use those U blocks open end up on top of your wall. Leave out the block every 8 to 12 feet where you will run rebar down to the footing. Lay 2 #4 bars on supports in the U blocks and tie them to the vertical bars. Use plywood to create a form where you omitted the U blocks and pour the tie beam and vertical columns at the same time. The upward U creates a form for you to pour the tie beam.
Jump right in here Glenn or John ... Good idea ... Bad idea ??
Good idea - the only reason I mentioned the cut out way was that he didn't want to raise the wall higher, but yes -- that would do the job. :)
Love your ever so willing to help work crew! Good luck on the roof. Engineered trusses should do fine once you have something to attach them to. I hope to see a roof on it soon with follow up pictures as you work your way thru to living in it.
QuoteThe vertical columns cemented wouldn't do much without the bond beam. Some but not much in case of earth quake. Maybe you don't have that problem down there - Unless you are in an area of subsidence because of oil pumping - that could break it up eventually. The bond beam could be put in by cutting about 1/2 or 2/3 the way down the blocks in the center and taking it ou with a hammer but I don't know about stopping the holes. A plumber I knew used to wad up news paper and jamb it in the hole then pour some flowable grout for plugging 4" waste lines. I think I have see them put a row of 30 lb felt or something to keep the concrete from going to the bottom but most jobs I am on are filled solid. I guess you could put felt in the channel made by breaking the centers out. Doesn't matter to me -- just throwing out ideas in case you want to use them.
Also I see you have a footing inside the wall - could you just put a pt plate and or blocking there to support the ends of your floor joists?
Hm ok I like this idea because it wouldn't require putting another course of blocks up and re-surface bonding the last row.
So I would put a block cutting wheel on my 4" grinder maybe and grind some slots going all the way around and then just knock out the partition segments. I might be able to cram the partition segments that I cut out in there to help stop the holes, and then maybe add some other stuff in there.
As far as just setting a PT plate on that footing and setting the joists on top of it, sounds like a good idea to me. I was going to screw a plate higher up and match the joists flush with it but it sounds like just setting the plate on the footing and putting the joists on top would be stronger. Sounds good to me, thanks for the idea! Even if I had to rip the PT plate to be the right width that would be easier than what I was going to do.
Ok one last question: on the PT plate I'll be bolting to the very top to give me something to secure the trusses to: How wide/ thick should this be? the blocks are 8" wide, should I just get a 2x8" If thinner, should it be flush to the inside or the outside ledge, or in the middle?
Thanks a lot everyone for your input it is helping a lot!
I like John C's suggestion for the bond beam tied into poured columns as the best way to stabilize the wall. You could pour exterior pilasters and tie them to the wall with anchor bolts tied to bars in the pilasters. Lots of work and material there however.
I like Glenn's suggestion of placing the floor bearing on the wide footing but there may not be enough room under the joists and beam (16" min under joists, 12" min under the beam). In that case you could do a PT ledger higher up the wall and then support it with a few bolts AND with PT legs down to bear on the footer. You can insulate the floor joists and screen those block vents and be home free.
For the top plate a PT 2x6 flush with the outside wall would be fine.
Thanks for the input guys. I think I am going to go with the bond beam/vertical columns after all. I will cut in though and pour it in the top course rather than add another course just because I don't want to have a big ugly seam going around where I came back and surface bonded the last row after having done the rest.
Next question: After doing some more reading, I think I am going to get myself killed if I have anything to do with getting 38' trusses on my building and getting them sheathed and secured.
Does anyone have any idea how much this costs to have done? At least truss erection/installing and sheathing? I can do the metal roofing myself I guess.
Also, who do I get to do that? What are they called, like "truss installation guys" or what? Will people come do a job that small if its just the roof or do they only want to mess with big jobs? I think i would be better off saving up for having someone else do it but I am not sure who I am looking for to do the job.
If you're having to save up you will have some time to do some local research. You should be able to find a local contractor. For a job that I didn't want to tackle (metal re-roof) we did the usual phone book cold calls and interviews/estimates. We als talked to a local custom builder and got the name of the guys he uses on the homes he builds. We ended up going with them inbetween roofs for the builder. They did a great job from what I can see.
One thing about metal roofs... they are much more slippery to work on than the typical granulated shingle roof. I've never felt too uncomfortable on my roof before the metal went on, but it's more spooky now and it's only a 4:12. But I wouldn't trade the metal for anything else.
I have a neighbor who recently finished a large garage. It's size and construction reminds me of your project. A couple of (young) guys did all the truss and roof installation. I didn't see the effort, but I think they attached temporary "stilts" to each of the trusses and pivoted the whole affair up atop the walls. As they moved the trusses along the wall, each truss had a temporary counterweighted "leg" hanging down to keep the truss from rolling over. As soon as a few were located, they did a lot of cross-bracing to make sure a breeze didn't upset everything.
When getting on my metal roof, I use several squares of rubber (interlockable edge) tumble-mats (is that what they are called?) to keep me from slipping too much.
Was it close to my house in size? The main thing that is making me wonder if I can do it is the size of the trusses. It seems they would be too heavy to manage without a crane.
Many truss companies have a crane to deliver the trusses and set them on the roof or know of one available. You would probably still want some experienced help there as they can be floppy and knock you off if they get away from you.
Having the layout lines an method of fastening and bracing planned, layed out and marked ahead of time will help.
I've occasionally seen them stacked together upside down on a roof. That would exert a lot of outward force on the walls. Is that a common practice?
I have seen it done that way - truss crane truck or reach forklift throws them up there then a couple guys move them along and roll them up into place and fasten and brace them off. I would assume the walls have temporary braces nailed to the floor to keep them stable.
Hi again everyone. So I had a lumber company tell me with their engineering stuff how to frame up the roof so I'm going to do that instead of trusses. I poured the bond beam recently by grinding out a channel with a grinder and stuffing some holes with tar paper as was suggested earlier in this thread. It worked well. The pour was a disaster though...had a big concrete pumping crane come and the guy wouldn't slow down the flow (aggregate didn't fit down between rebar so I had to push it through with my hands which ripped my hands up badly even though I was wearing gloves) and there was no way I could have put bolts down in the concrete before it dried since I was by myself until the very end. My hands are healing up well now and I'm ready do the next step.
So the question is: the next step on my roof is to mount the top plate (Pressure Treated 2x6 as was suggested in this thread). I am chiseling the top flat with an air chisel because it is somewhat bumpy. I'm almost done with that. In the absence of bolts anchored into the concrete, what is the best way to attach the pressure treated 2x6 to the top of the block wall? I have all my lumber on order and am just waiting to figure out this step before proceeding. I'm thinking something like a 2 1/2" concrete nailer from Harbor Freight http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=90342 and lots of Construction Adhesive, but I am investigating all suggestions before proceeding.
Thanks everyone for your help and input.
anyone esle do this? When I see a word that is new to me or I am only slightly familiar with; i. e. John said "flying buttress" I go to Google and on the IMAGES pages I do a search of it. Wow....look at dem Flying Buttresses!
I do this for lots of building things, lots of pictures....and each one is worth 1000 words....sometimes.
Yep, that's a great trick!
And then you can even pop the image into your post using the picture frame icon and look even smarter! ;D
(http://openlearn.open.ac.uk/file.php/1329/T173_1_060i.jpg)
Nice. Does anyone have any input on my question?
Thanks!
If all else fails, you can always install a tie-down means to the roof system after the trusses are in place. For instance; A long tie-down strap that begins at the inside of the wall, bolted to the footing ... goes up the inside wall, over the top plate, down the outside wall to the footing for anchorage.
A few of these, placed between trusses could keep the roof in place during winds. The straps need a slack take-up means on both sides of the walls so they can be left in high tension. Some engineering input would be needed for sizing.
A bit of cosmetic covering of masonry contact cement could keep the straps from view.
Is there a reason I couldn't use a bunch of tapcon concrete anchor screws? I just am not sure how determine how much holding power I need.
Tapcons are too small. You could either use 5/8 inch or so expansion bolts with washers or bolts such as PEG posted before which screw into the concrete like Tapcons but are larger.
Probably minimum of 4 inches embedment so I'd use about 6 inch bolts. You can rent a Rotohammer with a proper sized bit. There are several brands of bolts -- you just screw them in with an impact wrench. If you don't have an impact wrench then the expansion anchors such as RedHeads will work fine. Blow the holes out before installing the bolts.
http://www.itwredhead.com/trubolt.asp
(http://www.itwredhead.com/images/redhead/trubolt/tru_prod1a.jpg)
Apparently they now have LDT's -- large diameter Tapcons which are similar to the type PEG posted.
http://www.itwredhead.com/ldt_prod01.asp
(http://www.itwredhead.com/images/redhead/ldt/LDT(2).jpg)
Check out this related thread with me and my missing rebar - worked great.
http://www.countryplans.com/cgi-bin/yabb2/YaBB.pl?num=1184979778/5
QuoteTapcons are too small. You could either use 5/8 inch or so expansion bolts with washers or bolts such as PEG posted before which screw into the concrete like Tapcons but are larger.
Probably minimum of 4 inches embedment so I'd use about 6 inch bolts. You can rent a Rotohammer with a proper sized bit. There are several brands of bolts -- you just screw them in with an impact wrench. If you don't have an impact wrench then the expansion anchors such as RedHeads will work fine. Blow the holes out before installing the bolts.
How do you think would be best to space them, and in what pattern? I have 150 feet of this to do so I want to keep the cost as low as possible since I'm on a budget but I also don't want the roof flying off in a storm or something embarrassing like that.
I was thinking I think I will go with the Large Diameter Tapcons, because they look like they would pose the least interference with the rest of the framing job. They look like they won't stick up as much. Hopefully I can find them at Home Depot. I have a bosch hammer drill http://www.internationaltool.com/hammer.htm like this one that has handled drilling lots of 1" holes in limestone and concrete so I thankfully think I can use that for driving the tapcons and doing the predrilling.
Thanks again everyone, this input is very helpful.
Another anchor method available to you: Use a carbide bit and drill thru, horizontally, some select locations (voids) of some of the first course blocks. Then a faily inexpensive regular bolt, with nut, put thru the wall, will give you a nice anchorage. Not the footing ... but I bet the bottom of that wall will never move very far.
I don't know if you have a code to meet or if you can since they were not in originally. Some of the info I have seen says minimum 1/2 inch anchor 7" deep at max 6' OC and 12" from each end. Another place recommended every 32 inches - another place said 4 inches embedment.
If there are any officials wanting to spec max distances I would ask them. Use washers also.
QuoteI don't know if you have a code to meet or if you can since they were not in originally. Some of the info I have seen says minimum 1/2 inch anchor 7" deep at max 6' OC and 12" from each end. Another place recommended every 32 inches - another place said 4 inches embedment.
If there are any officials wanting to spec max distances I would ask them. Use washers also.
Ok that sounds good to me, thanks! One last thing...am I just going down the middle of the 2x6 or do I need to do two for each place I bolt?
Fortunately there are no officials that are inspecting this operation.
One down the center - each place will be stronger than the wood anyway.
Hi everyone.
Wow those redhead anchors are sweet. They are very easy to use, priced reasonably and feel very sturdy.
I have my top plate all on and am most of the way done w/ my ceiling joists.
Here is a pic. I just have to go pick up a couple more 2x10x20's (I am short four ceiling joists) and then I'm ready to start doing rafters....however that works. I'm not sure what holds up the ridge board before you put the rafters on, but hopefully that will become evident with time.
Is there an easy way to attach more than one picture to a post?
Temporary braces hold the ridge until you have enough rafters in place. I'm sure PEG will have a photo ot two to illustrate. I know there are some photos illustrative of the method someplace on the forum, but don't have a clue where. :)
As for posting pictures the best way is to open a https://www.photobucket.com account. It's free. You upload the pictures to there, can setup folders for different stuff. Then you copy the IMG CODE tag (bottom of 4 choices) and paste that code in the message. When someone views the post the system grabs the image from photobucket and shows it in your message.
There's some image posting info here http://www.countryplans.com/cgi-bin/yabb2/YaBB.pl?num=1115032671
Any subfloor on top of those joist?
If not trow some sheet up to make a deck to work off.
Temp up your ridge "close " and put one rafter up fasten to the wall plates , then to the ridge . then do the other side rafter the same way , plate first , then break the ridge brd free and move your ridge to meet your other rafter. Temp brace so it doesn't just fall over , then go do the other end the same way. fill in , in between . do a set one each end working your way back from both end of that section of ridge . You do not need the full lenght of ridge up in place before you start.
(https://i21.photobucket.com/albums/b299/PEG688/apr134.jpg)
Two guys can do it three is easier , beginners might want more . We (two of us ) framed that roof up on a windy winter day , it was hoot! bolwn about 30 MPH with gust to 40 or so IIRC ;D
I'd recommend you pick a nicer day ;)
On # of photos I just keep posting them , stack them one below the other , not side ways when you insert them . I don't think there is a limit per post like on some other forums . If there is I never hit the limit and I 've posted a lot of photos in one post.
G/L on that roof , PEG
On the photos - don't use the little box on the compose message box. Use the Photobucket Don mentioned above -then multiples can be done as PEG mentioned. :)
Ok that sounds like a good way to do it.
I'm going to start bright and early tomorrow but I have two more questions.
1. What kind of board should I use for the ridge board? The lumber company gave me all kinds of stuff but I don't have anyway of knowing what piece(s) are for the ridge board. Is it a 2x6? a 2x8? 2x10? The rafter boards they gave me are 2"x6"x22' and the span of the roof is 39' and the slope is 4/12.
2. How much should the ridge board over hang the end of the house? When I built my daughters little 4' high play house, I didn't overhang the ridge board at all and realized too late it was a mistake.
Ok one more question.
3. To Simpson tie or not Simpson tie? I went ahead and bought some simpson ties type RR (ridge rafter) http://www.strongtie.com/products/connectors/RR.html to connect to the after to the ridge board. I realize now that using these will preclude using a framing nailer (If I'm wrong here please let me know), and will necessitate gobs of nailing by hand. Do simpson ties make it any easier to frame a roof for the first time, and do they give you more 'leeway', or are they solely beneficial for the additional strength they provide? They weren't that expensive and we have had some rowdy weather lately that made me wonder if my roof would be ripped off one day, so I thought I would pick some up and decide whether or not to use them when the time came.
Thanks everyone. I am really excited to finally be at this stage and I appreciate everyone's help with clearing up the details.
Quote
A: [highlight] I have two more questions.[/highlight]
Humm looks like more than two , you even wrote 3. ;D
1. What kind of board should I use for the ridge board?
[highlight]The 2x8[/highlight]
2. How much should the ridge board over hang the end of the house?
[highlight]Seldom does the ridge itself overhang , it can overhang but it is not absolutly neccessary. On most truss roofs there is no ridge board , you use let in "outlookers " to extend the eaves.
Common eave overhangs are 12" , 18" and 24". So it depends. Yes Glenn breakum out again! [/highlight]
3. To Simpson tie or not Simpson tie?
[highlight]Never used them with a ridge , I have used similar rafter ties where a shed roof and ledger where in play. IMO they will make the job harder, and not increase the strenght factor.
Use 16d nails the first one gunned right thru the ridge brd , the other nails driven at a angle right beside the just out in place "other side rafter" in a 2x6 you should get three 16d in each rafter , you can nail above the ridge and down into the second rafter of each set. [/highlight]
Do simpson ties make it any easier to frame a roof for the first time,
[highlight] Don't know but IMO they'd be in the way.[/highlight]
and do they give you more 'leeway', or are they solely beneficial for the additional strength they provide?
[highlight]IMO no additional strenght could be gained over proper 16d placement. And if you use a gun , have a hammer handy as gns just don't suck things together like a hammer does , done be afraid to beat the livin daylights out of things to move a rafter down , the ridge over , tame a big crowned ridge , etc . Show the wood who's the boss![/highlight]
quote]
You should get and use some H1's and where a H1 will not fit use H2.5's to tie the seat cuts to the top plates. Up lift is the roof destroyer in high wind, the ridge area / connections seldom, if ever , fail. The key is holding the edge / soffits down and connected at the top plates.
G/L PEG
Here's few more photos , you may be able to see the nail heads going thru the ridge into the other side rafter.
(https://i21.photobucket.com/albums/b299/PEG688/July251.jpg)
Also note the ridge is not one piece in this case , code here requires the whole lenght of the ridge cut be supported , you don't have code issues so if that 2x8 doesn't totally fill the ridge cut do not sweat it , thousands of home s dot the nation who have either no ridge board at all , just butted rafters , or 1x ridge boards , pieces of siding etc.
That ridge is a 2x12 with a 2x6 , ripped down to 4 1/2" IIRC. Total waste of good wood IMO, but it meets code ::)
One key to strong roof is good cuts and a good collar tie system, that collar tie makes a triangle which adds tons of strength.
(https://i21.photobucket.com/albums/b299/PEG688/July2610.jpg)
Note that nail pattern , thats your biggest strength booster, the properly nailed collar tie. In the old days , generally , the collar tie was a 1x6.
I don't think the nails I put my nail gun are graded like 16d, they are referred to by gauge. My nailer is an 8-10 gauge nailer. Is that 16d?
Thanks for the other info, I will reconsider using the rafter simpson ties. I did pick up some of the rafter-to-top-plate ties you are talking about and will for sure use those.
One of the reasons (gasps from all the experienced builders) I thought the simpson rafter ties might be good is because in case there are some gaps from my rafters it would still hold it on good. I think I will probably play it by ear, and if the rafters are working out well then I will forgo the rafter ties but if I'm having trouble and think it might not be strong enough then I can start using them.
What gun is it? If it's a framing nailer it will shoot 16d nails , BTW I never buy "true" 16d nails for our guns I get 12d's just a little shorter 1/4" IIRC they drive easier and do the same job , just easier. ;)
I'm sure if Manhatten where still here he'd freak out , again ::) Eh Glenn ;)
Depends, -- we gottem. :)
(https://i35.photobucket.com/albums/d184/glennkangiser/glenn-depends.gif)
It is a harbor freight gun I got for 50 bucks. It has worked great. http://www.harborfreight.com/cpi/ctaf/Displayitem.taf?itemnumber=93912 It is like this one except mine adjusts for different degrees, though I keep it at 28 degrees.
Notice how it refers to the nails as 0.113" to 0.131" instead of with D's.
if 16D is the 'standard' framing nail that is probably what I am using.
If your cuts are that bad buy a flat strap that can be nailed to the top of the rafters and run it up one rafter over the ridge and down the other side. They sell a coil strap that would be perfect for that. The collar ties you should use , and with that strap over the top say a 36 " long piece your cuts could be really $hitty and still you'd have a lot of strenght.
Yup that'll work.
Hey be safe OK , it ain't that hard , BUT things can get funkie fast if your not used to heights , ladders , etc . So think it through and give yourself a good "out" if it goes to $hit on ya ;)
BTW jumping to the ground is not what I consider a "good out" . ;D
PS Thanks Glenn ;D
Manhattan would have rated well on our inspector from hell list. He had the knowledge but no tact -felt he didn't need it as god had sent him here---- . If you can't deliver your message of instruction tactfully, then people will turn you off rather than learn from your experience. He refused to learn that so I had to turn him off.
We don't have to put up with that. No power trip here for him. ;D
BTW, PEG. I'm always here for you with the Depends when you need them. :)
Ok great. Now I feel better about forgoing the simpson rafter ties. I have no reason to believe my cuts will be bad; just allowing for the inevitable 'Oh my gosh, i didn't think it could be this bad in my worst nightmare but yet here it is in front of me, what do I do now?' scenario.
I will be careful; nothing can be as bad as the bond beam pour in terms of risk, pain and suffering. The pump crane operator hit me on the head w/ the boom and darn near knocked me off the wall.
So tomorrow morning I will traverse to home depot and pick up a new box of framing nails (the only ones I have left are too short I think) and give it a try w/o the rafter ties. That will save a lot of work so hopefully it will turn out ok. I have a swanson speed square and the accompanying blue book that I hope will help me make the right cuts.
I'm out for tonight. I took this whole next week off of work as vacation days to try to get as much done as I can so hopefully it won't rain all week.
Thanks again! I will update w/ pics after I get a few rafters going to see how it looks.
QuoteIf your cuts are that bad buy a flat strap that can be nailed to the top of the rafters and run it up one rafter over the ridge and down the other side. They sell a coil strap that would be perfect for that. The collar ties you should use , and with that strap over the top say a 36 " long piece your cuts could be really $hitty and still you'd have a lot of strength.
Not to say that my cuts aren't / wont be perfect ;) but... is that coil strap stuff like what you would find to hang pipe or ducting? or is it a heavier gauge?
Thanks
Quote
#1: but... is that coil strap stuff like what you would find to hang pipe or ducting?
#2: or is it a heavier gauge?
#1: No Simpson does not sell pipe tape , which is what your talking about.
#2: Yes ,
http://www.strongtie.com/products/cfs/cs-cmst.html
(http://www.strongtie.com/products/cfs/cs-cmst.html)
They don't show a photo of it being used as I have stated but with that strap over the top tieing two rafters together , in conjuncture with a collar tie you'd have a very strong system to resist downward forces and the spreading of walls that those forces are working on.
It will create other issue as in nailing your roof sheathing where the straps are. You'd MTL have to drill a hole thru the sheathing and the strap then drive your nail thru both at once.
Good cuts and proper nailing would be the best option.
Sans heres a example of a 1 by ridge as well as a 1by ridge that doesn't fill the whole ridge cut.
Hip roof , house built in 1947 or so, 1 x 8 , made from shiplap sheathing , ridge and 2x6 and 2x4 rafters , the rafters are over spanned even for 20 years ago , with todays wood SPF or even D Fir they'd be way way way over spanned.
(https://i21.photobucket.com/albums/b299/PEG688/Sept820071.jpg)
This shot shows a gable roof with the 2x4 rafters and a 1x8 ridge ,
(https://i21.photobucket.com/albums/b299/PEG688/Sept820073.jpg)
Jack rafter dieing into a hip ridge , note the 3 ea. 16 d bright nails , in those days brights where the framing nail of choice before the Ca. boys started the "gas and wax' 16d which the modern day sinker was developed after.
(https://i21.photobucket.com/albums/b299/PEG688/Sept820074.jpg)
Things to notice are the cuts where good and have stayed good. Even the rafters that are not supported all the way on the ridge cuts still look like they did 60 or so years ago.
No collar ties , but remember this is a hip roof so downward pressure is spread / shared differently than a gable roof . A hip is considered one , if not the strongest roof lines.
They also used 1x 6, 8 , &10 shiplap for sheathing on the walls , floors and roof. So of those boards where used on the foundation as concrete staining can be seen on them.
Thanks for the pix, PEG. You mentioned that the old boards were over-spanned. Did you notice any sag in the roof?
Oh ya it's sagged some , it's my roof , it's strong enought , the rafters have just sagged some. Feels fine when you walk on it but yes they have some sag.
Thanks -- just wondering. Our other house -- a real house -- not a cave, has sagged a bit -- a hip roof also built in 1952. Also - not a problem. Redwood siding all around the original part.
Ok guys, I'm having trouble. I used the swanson speed square blue book thing, to calculate the rafter cuts.
It turns out my building's span is 39' 6.5" instead of 39'. hee hee my mistake.
If I use the blue book table values for 39' + 6", do I need to worry about the 1/2" of span not being accounted for? I cut two rafters based on 39' 6" and they aren't really fitting but it seems like 1/2" isn't in the blue book and would be so miniscule that it wouldn't make as big of a difference as I am experiencing.
When I try to put the rafters up, do I nail them to the ridge first and then the joist, or vice versa? Nothing is really adding up and I can't tell if they are too short or too long or what the problem is. If I nail one to the ridge board and the joist and get it to the right rise height, it looks fine w/ no gaps. Then I try to attach the opposing rafter and it has to be pushed back toward the top-plate (making the birdsmouth not on the top plate hardly at all) in order to match up to the ridge board.
I tried to be very careful w/ the calculations for the 4/12 slope, 39' 6.5" span but I must have made a mistake somewhere. Can someone check me?
Here's what I came up with.
Rise: 6' 7"
Rafter length:20' 10"
I remembered to take out 3/4" to accommodate half the width of the ridgeboard, so that makes the rafter length 20' 9 1/4".
the little angle thingys I followed the blue book and am pretty sure I did those right. I think the degree angle was something like 19.5.
I just went up again and took the ridgeboard out of the picture altogether, and the two rafters overlap eachother by about 1 1/2". birdsmouth and angles all look fine except the rafters just seem too long. I guess I could just cut them but it seems like I should be able to figure out why they are longer than they should be. Also I don't want to cut up my $900 dollars in rafters and find out I did something wrong.
Sounds like you did NOT reduce for the ridge thickness. 1 1/2" ridge = reduce by 3/4" on each rafter.
I am sure I did. I even rechecked calculations and re-measured my template. They are overlapping eachother by 1 1/2", so if I trimmed 3/4" off each, they would be even w/ eachother, and there still would be no room for a ridge board.
I think my angles are all a little bit off or something. I rechecked my ridge board angle and it was a little bit off. This accounts for the gap shown in the picture of the rafters connecting to the ridge board.
I ended up pushing the two rafters up into the air, pivoting off the seat cut until there was a 1 1/2" gap between them. It worked out ok I guess, everything has a little bit of a gap but I guess it is close enough. The seat cut is off the top plate a little (from lifting the rafters higher to eliminate them overlapping so much that the ridge board wouldn't fit between them), but I figure maybe it can just droop down over time.
Can you check out the attached picture and tell me if this is cause for concern? I intend to adjust my template a little bit on the next two rafters and see if I can get it closer. If it doesn't make an appreciable difference then I'll just cut all the rafters at once. haha At this rate it will take me 50 days to do my rafters! Hopefully I can become more efficient on the next few.
By the way, the line that you see on the seat cut is from an old measurement, it wasn't the line I was cutting off of. That seat cut is a little mangled because I had to yank it out and it ended up splitting it a bit...maybe closing the gap a little! Also, "Rafter 2" looks like it is too high above the ridge board but that is because the ridge board had a big bevel on that edge.
(https://i35.photobucket.com/albums/d184/glennkangiser/rafters_composite.jpg)
Edited to move image to photobucket - GK
So to be clear you only have two rafters cut right now?
Where did you measure ? There is a thing called the "measuring line ? maening you need to measure parrell so you need to measure from the crotch of the seat cut to a point the same distance from the rafter bottom.
It's hard to explain that measuring line thing .
Do you have a steel square ? I helped youngins with his little roof and wrote and provided photos on how to "step off" rafters. I never measure mine , but I do check that number after I step off the rafter, just to compare the two.
Check out yougins thread about putting a roof on or some such.
Generally I check one pair of rafters at each end of the building if I like the look the first one I layed out becomes a pattern , I choise a good straight rafter to lay out first thing and make it as "Pattern".
How does the building measure up ? Is it the same exact measurment on each end ? If it is once your happy with your rafters cut them all , you can move the ridge to where it needs to be that way.
If your building is all over the place in size / measurment , your screwed I can't explain how to fix that.
Just two rafters are cut right now...well, three. Two are up on the house and one is my template. I think I have 8 extra rafter boards to burn through before I will be short. My building is the same span on both ends fortunately. However the plate that I bolted onto the top of the block wall swerves a little due to warping but but it should be well under 1/2" variance.
I searched for but could not find the 'youngins' thread about putting a roof on. Can you post a link if you are able to find it?
I think I know what you are talking about. where you don't measure the rafter but hold it up and trace the marks? We did that on my daughters tiny 4' high play house. I didn't think to try that in this case because the rafters are so long and I'm working by myself so I wasn't sure if I would be able to hold it exactly right to make the marks.
I do have steel square (and an aluminum one too!)
Did the pics I posted look like they were within acceptable tolerances in terms of gap? It didn't look that bad to me except I keep seeing everyone elses perfect rafter pictures!
I am going to try to adjust my angle a little to fill in some of that gap. Basically All I did to get it from overlapping 1 1/2" to having that small gap was just pushing the rafters up. If the gap is ok, I will just continue doing what I'm doing and make some adjustments as I go to try to make it smaller. The gap I think was like 1/4". The rafters are 16" oc in case that information factors into what is acceptable.
Looking at the Birdsmouth and seat photo.... You should cut to the line with the circular saw and then finish the cut off with a jig saw, sawzall or hand saw to avoid that strength sapping over cut.
Here's that link
http://www.countryplans.com/cgi-bin/yabb2/YaBB.pl?num=1185561119/0
I think
#1: are you sure your birds mouths are up tight to the wall? If they are not pull up on the ridge would close both gaps , the BM and the ridge cut. '
#2: if your up tight I'd take a saw cut from nothing at the bottom to 1/8" , maybe a touch more at the top , to fair that cut in. If you did that you'd be lookin real good.
#3: Your cut , as they sit arn't that bad , BUT things like that tend to grow , not get better . So the beter the first pair look , the better they all will look in the end.
#4: I'd try step #2 above before you do anything else. I think that might solve your issue.
Youngins roofing thread
http://www.countryplans.com/cgi-bin/yabb2/YaBB.pl?num=1185561119
Thanks guys. I will workwith it some more tomorrow and hopefully get it closer. I'll post some pictures tomorrow of the perfectly fitting rafters I'm anticipating.
I was wondering about the overcuts myself too. I will try to get a hold of a hand saw to avoid them. I didn't like them either but didn't realize it would sap an appreciable amount of strength from the board.
Forgot to update w/ the results. Turned out pretty good although it was plenty time consuming for me to do it by myself.
We got carried away and added another room up top because we had lots of wood laying around we had already paid for.
Thanks everyone for all your help.
Looks good. Looks like the top room may like some rafter ties or something to keep the walls from pushing out sideways.
Well, I glued up a beam for the top room hoping that the rafters would just kind of hang on it instead of pushing on the walls. The reason is head room. Do you think that w/ 2x6 w/1/2"plywood glued/nailed into a beam that it will spread? That would be scary. The beam is like 12 or 13' across so I was hoping maybe that the beam would be stiff enough to not allow rafters to spread walls.
Here is the beam in this pic. I slathered some more weatherproof titebond on the top to help protect it from weather.
What I think I see in the picture is that the ends of the beam don't go to a solid ground support -- all the way down -- so it can still sag.
If you could put collar ties a bit down without destroying your head room that would help -- they are shorter and higher than rafter ties. You could gusset the collar ties to make it more of a truss giving more of the strength of the rafter rather than pushing and spreading by shoving against the ridge beam.
Sheathing the endwalls and nailing as for brace panels could also help with the beam support, but for it to work the load needs to somehow transfer to the foundation and ground. Posts would be ideal but maybe not possible due to what is below. Filling in the open spaces with posts could transfer the weight to your block wall on the end it looks like.
Gluing the plywood gussets at the collar ties will help also. Making them as big as possible will also help.
Maybe I'm being overly cautious but it looks like an issue worth taking care of to me. :)
The issue I see is not the beam but the idea that the beam is not supported at the ends to the ground through one path or another.
Only indirectly over studs through the top plate and I assume the other end is over open space of a room below can cause sagging of the wood, beam and spreading of the walls.
I think I'm confused a little, are you talking about spreading of the main walls of the house, or of the walls of the little top room?
The little top room.
oh ok I think I see what you mean. I am going to put some posts under the triple rafters under the beam and put some studs right under the beam resting on the triple rafters going through the floor down to the bedrock, I just haven't figured out how to do it yet. I guess I can build up a post or something, nothing I have laying around is tall enough.
Any way to properly transfer the load should work. Mostly just look at it thinking about where the weight from your snow load 20psf? -and floor loads and dead loads - weight of building materials etc. would go if it actually got loaded that heavily. Then decide how they will be supported to the ground.
Glenn makes some good points there.