24x32 in Southern Illinois - New member.

[interex]

Just to make sure I get the right joist ties... Are the Simpson Strong Tie Hurricane Z-MAX ones from the link below okay to use, to secure the joists to the beams?

http://www.lowes.com/pd_90575-72913-H1Z_0__?storeId=10151&Ntt=90575&UserSearch=90575&productId=3047195&N=0&catalogId=10051&langId=-1

[Squirl]

I believe those are some of the stronger standard hangers simpson makes for uplift.  Also they give better lateral support many other hurricane ties that size.

http://strongtie.com/products/connectors/H.asp#tables

It looks like it is stronger than many, but less than all.  It depends on the application.

[John Raabe]

That would be a good choice.

[interex]

Thanks for the replies.

I'm going to just get the Tyvek and roll it out and staple it to the beams, then install the 2x8s.

Then this weekend I will run the water/waste pipes, then insulate and install the flooring and just tarp the floor if it looks like it will rain.

I will only need to T off the water pipe going up into the bathroom, then over into the little kitchen as we have 2 small tankless electric heaters to supply both areas.

[interex]

Okay, so today I decided not to put down the Tyvek and started working on my joists.

I have triple checked my beams over and over again and they have maintained a very fair amount of levelness.

Tonight, I installed 3 of the joists and they all seem to be fairly level with eachother, except one, which shows it is much lower than the others in one spot, not the entire length.

I'm starting to get worried about it, but someone else tonight told me not to worry about it.   Is this a sign of undersized 2x8s or possible warping?

Another thing I'm thinking of, while I'm at it...  what does everyone do to cover/hide the posts?  I can't use blocks because there won't be any room, and I don't really like underpinning all that much.

I could go with something like half log, or quarter log from the beams all the way to the ground, but that may not even be the best idea... I really only have about 1 and a half, to 2 inches to work with the north and south walls, and about 2.5 - 3.0 inches on the east and west walls, at the footing.

[Don_P]

Sight down the length and crown all joists, or horizontal members, up. Pich a crown direction and have a "rule" for studs crowning them all in the same direction. If there are any joists that are significantly off either reject them or slide your level around on its neighbors while planing, sawing or hewing it down to level.

[Squirl]

I've seen them hidden by almost everybuilding material under the sun.  Don't use OSB.  One person I saw on here used rocks built up like a mortarless stone wall.  My preference would be pressure treated 1x boards or PT plywood.

[interex]

This morning I was actually thinking about PT plywood and some really thin white stone mortared to it... But I dunno anywhere locally who sells stones like that cut so thin.

[interex]

Okay, so lastnight we got the joists all done.

I noticed that the last 3 or 4... we didn't keep them straight and that have a very slight angle to them... and I have no idea why... might be that my guide board warped in the last day or so, but I don't think it will hurt too much.

I didn't get a chance to get a picture because it was after 9PM when we finished, but hopefully tomorrow I can get some.

Before I lay down my sub floor, what is best to put atop the joists?  felt paper?  And what thickness of t&g plywood should I use?

[John Raabe]

Use a 3/4" T&G subfloor panel. Install with the appropriate space between the joints. Many people will put down the T&G with construction adhesive and ring shank nails or screws.

Here is more step by step info: http://www.diyonline.com/servlet/GIB_BaseT/diylib_article.html?session.docid=1463

Your lumber yard may have more specific information on what products work best locally.

[interex]

Just for knowledge sake...

How thin can wood siding be on the outside?

My local saw mill said that 7/8" is good for homes around here if properly treated... but I want to ask here.

The saw mill can cut 7/8"x12"x14' at $0.45 per board foot, making it about $4.73 per board.

[Don_P]

Check your math, he'll be billing for 4/4, or 1" thick, X1' wide X 14' long X.45 =$6.30 per board.

That will be fine thicknesswise, do plan out your window and door trim, likely 2x material. Many old farmhouses here are slapboard sided with 5/8x6" poplar siding. I've removed some from as far back as 1865, it was done but had held up for a mighty long time.

[interex]

He said they would bill at the exact board foot measurements or 3/4 or 7/8 inch, which ever I choose, not rounded up if I ordered large quantities.

I will double check to make sure tomorrow, but even if I went down as low as 5/8 or 0.63 inches... and they didn't round up, that's an even bigger savings.

Also, is $0.45 per board foot good or too high?

[Ernest T. Bass]

Sounds pretty good to me, depending on the type of wood.. We pay $0.35/bf for rough-sawn spruce, (and it's really roughly sawn...). Twice that for cedar.

[Don_P]

It does depend on species and grade but that is quite reasonable. Generally 4/4 and below gets billed as 1" thick so he's also being quite reasonable if he's billing for exact thickness. I paid .50/bf just for portable sawing service last year, my logs.

I wouldn't go down in thickness at that width.

[interex]

His price is $0.45/bf for his logs, or $0.25/bf for my own logs.

We have several acres of trees but none that would be that beneficial for our cabin.

You're saying 5/8 is too thin for 12" boards?  What about 5/8 for 8-10" boards?

[interex]

Okay, so I've got my foundation all finished, all my joists tied and boxed in.   I have purchased 18 sheets of advantech 23/32 plywood (subfloor) and 2 rolls of 15# felt paper.

I'm ready to lay my floor down but lastnight I spoke with my general contractor friend and he was asking about the beams I want to run above the loft, the 32' span (longways).

I have posts to set the beams on but there will be close to a 24' span over the main area where there won't be any posts to rest the beams on...  so my question, or concern is... how big of a beam would I have to make or use in order to have the proper support over this 24' span?

My friend said to build a plywood box beam, but still said he was unsure if that would even be enough.   I was thinking about making  4x10 or 4x12 beams but need to know what the forum thinks about this.

We figured out roof pitch would be close to 6/12 and while it does snow here during the winter months, it isn't generally enough to really bring a lot of concern with.

[John Raabe]

You need to get some local engineering help with the beams and posts before you go further.

The engineer will do a load trace following and accumulating the loads of the roof down into the planned beams. Then those beams need to be supported by posts and foundation pads. The sizing of a beam with a span of 24' is likely to be quite large and its support will be an important part of your design. This is well outside any "rules of thumb".

[interex]

All 6 posts going up to support the ridge beams will be sitting on top of the concrete piers underneath.   The piers are rather large as stated previously back in the thread.

The only other option I have is to run a single ridge beam at the very top center instead of running two 8' in from each side.

I dunno which would be better though, I thought running two would be easier, and give 8' span between the beams in the loft, and still look nice.

I don't currently know any engineers who could help me figure out the ridge beam issue.

[Squirl]

You are definitely in engineer territory.  24 feet is a pretty extreme span for any beam, especially in a snow load area.  In my calculations, I couldn't find any engineered beams that fit. The largest size beams in code charts on only a 20 ft wide building is rated for 14'-1".

In addition you need to check the load to the piers and soil.

Soil load is rated in psf.  Averages range from 1500 to 3000.  Even at your pier size with a 24' span on only a few piers, it sounds like you are exceeding the rating of most soil.  You have to calculate the load from the roof, plus the load from the floor on those piers, divide that by the square feet of soil that each footing rests on.  If that is greater than the bearing capacity of your soil, you have a problem of those piers sinking.

[interex]

Okay, so a single ridge beam at the top center to tie the rafters together is better than trying to run 2 beams 8' in from the outside walls and resting the rafters on top of it?

Just trying to make sense of this.

[Squirl]

Neither you are trying to put too much weight with too little support.  A 4x12 would be so severly  undersized for that span as to risk failure. I am trying to say that without understanding the principles of the design and load distribution, an engineer is needed.  You are taking your life or someone elses in your hands if this collapses.  My recommendation is to not just wing it.

Danger Will Robinson.

[Squirl]

To put it in perspective you are distributing tens of thousands of pounds of roof load or 3/4 of the roof load to six posts.  In addition these posts piers will be holding some of the floor load.  While concrete is rated to handle that kind of load, wood and soils are not.

[interex]

I'm asking about doing a standard rafter setup, like this...  disregard the 2 beam setup from before.

My outer walls should be able to handle this.

[dug]

The example shown is a standard ridge board with nothing I can see to tie the walls together except the rafter tie in the foreground. In the loft area the joists should run the other direction and tie the load walls, and rafter ties need to be on every rafter in the open area. I built my roof this way and used beams only every 4 ft., but I learned here recently that IRC now says ties on every rafter.