Sheathing question

AndrewPhelan · September 05, 2007, 02:36:11 PM

I had these questions in the owner projects category, but I figured the proper place to put them was here. Pictures of this project can be found in this thread:
http://www.countryplans.com/cgi-bin/yabb2/YaBB.pl?num=1189016857

Construction is going faster than expected, and I have a few questions that I'm going to need answered soon so work can continue.
1) My beams are pressure treated but my floor joists aren't. I don't think this is a problem as there is more than 2 feet between the joists and the ground; I believe I read somewhere that if wood is more than 18 inches off the ground it doesn't have to be pressure treated; could someone please verify this?

2) I am going to be attaching a wrap around porch sometime within the next year; my original plan was to run sheathing (and HardiePlank) to the subfloor level leaving the 10" of joists exposed. Then I would attach the deck to the house with hangers attached to the floor joists. Will this be OK, or will I have rotting issues? I guess the question boils down to: do I need to run sheathing to cover the joists?

glenn kangiser · September 05, 2007, 03:51:00 PM

1. That should be no problem as I remember.

2. Something will have to be done there. PEG is best on this but probably continuing your felt down and your siding to the bottom then PT ledger may be a good choice. I would think sheathing and water protection/siding to protect the untreated wood. PEG has posted lots of pictures of water damage in places such as that. Again - I'm just a steel guy who watches a lot of these projects - others can give you better info.

September 05, 2007, 04:28:45 PM

#1 is no problem

#2 is a very good question. I'll defer to PEG as I haven't checked into the fine details on this.

But I do believe something must be done to be certain to exclude water from making its way into the flooring. If there's a way water will find it.

AndrewPhelan · September 05, 2007, 04:49:00 PM

Thanks for the quick responses...they're helping, but I have a little more to add:
The reason I wasn't planning on sheathing and siding around the floor joists is because this is where my deck is going to attach. It seems like it would be awkward attaching the deck to an area on the house that already has siding on it. It also seems like this wouldn't be a wet area as the porch is going to be covered...but I have no construction experience and need some advice on how to proceed. Can I just run sheathing and felt over the joists, but not put siding there so I can attach the deck easier?

MountainDon · September 05, 2007, 05:25:09 PM

I had a question and forgot it earlier. Not a big deal.

Is the porch floor going to be lower than the interior floor? This would be normal practice if the porch was exposed to weather.

By a covered porch, do you mean sealed, windows, etc. or roofed over but with the possibility of rain/snow coming in through open spaces, screens, whatever?

If there's any chance of water getting in somewhere at any time it's a concern. I live in the desert, very low rainfall totals. But sometime over 20 years enough water got into a small space on one of my covered porch areas and caused a section of a beam to rot. (porch with roof only, no windows, no walls other than the house wall). It took a while I guess, but by the time I discovered the rot it covered a fairly good sized piece of the beam. Fortunately it was not all that difficult to replace, but I wasn't happy.

September 05, 2007, 05:48:32 PM

Even covered if open, it could get water problems. Rain blows horizontally here.

MarkAndDebbie · September 05, 2007, 06:21:19 PM

1. Depends on where you are. In New Orleans you might want treated (maybe borate) for the whole structure (those flying termites).

PEG suggested at one point that you could help everyone answer your questions best by editing your profile with a little information about your project (location, type of building, etc). To edit your profile click the "profile" icon at the top of the page and then choose "modify" in the top right hand corner.

Welcome to the boards and good luck!

PEG688 · September 05, 2007, 10:07:07 PM

There's a few ways to do it. But you do want at least building felt / or Typar / Tyvek behind that rim.

You could side all around the place and bolt that deck rim right thru the siding.

Thats generally a remodelers way . Siding already there so bolting thru is OK.

New work we'll generally run sheet metal , comes in wide rolls , 6" , 12" 18" & 24" up the wall , building wrap / felt over the top of it leading the water out not behind the metal decide where the ledger wiil be and bolt it on , then side around that ledger, keeping in mind the added materials / ie decking , end rim joist for the deck , etc when you space the siding around that ledger, if it's high exposure we'll slip a counter flashing up under the siding , generally called a drip edge , that kicks the water away when it runs down the siding.

Two rims ready for future deck and shed roof above said deck.

This photo you can see a "Z"metal under the lower part of the rim and over the siding below , again leading the water out.

Deck rim joist that white looking thing just under the decking is a "Z" metal , it's under the siding above and over the rim to shed the water out onto the siding face.

All the same house , different year .

All that being said , I kind a like rot , pays the bills yanno

As long as it caused by some other carpenter/ company , I got no problem with it.

PEG688 · September 05, 2007, 10:09:56 PM

Quote

PEG suggested at one point that you could help everyone answer your questions best by editing your profile with a little information about your project (location, type of building, etc). To edit your profile click the "profile" icon at the top of the page and then choose "modify" in the top right hand corner.

That was first suggested by Dave LeBlanc , he's no longer with us.

September 05, 2007, 10:24:26 PM

Quote.... I kind a like rot , pays the bills yanno As long as it caused by some other carpenter/ company , I got no problem with it.

In the PNW how many years would you say it takes for you to profit from the errors of others, re rot replacement?

PEG688 · September 05, 2007, 11:20:25 PM

Quote
Quote.... I kind a like rot , pays the bills yanno As long as it caused by some other carpenter/ company , I got no problem with it.

In the PNW how many years would you say it takes for you to profit from the errors of others, re rot replacement?

The rot shot above was on a 8 year old house. The one on the beach from earlier this summer with the rotten LVL was 12 years old .

The farm house window I repaired was MTL 40 plus years old. Old wood , older , less insulated / less tight houses fair better / rot slower.

New wood like we're using today and insulation(holds water really well) rot quickly. Mold , mildrew etc. I'm not new to this game , I'd have more photo's of rot but my camera is only 3 years old , I never took this many photo's before , it was to costly , hard to get it all done / developed etc , with the net and digital camera it's so easy to documnent repairs it's not funny. Great for insurance work as well , adjusters love it.

MountainDon · September 05, 2007, 11:23:26 PM

Paul,

Would you something like this would work?? :-/

Metal sheet down the rim face, starting under the sheathing to keep the water out of the floor. Then a Z-strip under the siding and under the #30 felt so any water there gets led out and away.

Would galvanized or aluminum be your metal of choice for the wide sheet metal?

PEG688 · September 05, 2007, 11:35:56 PM

Thats a keeper Mtn D 8-) Nice drawing 8-) Generally a brown / bronze colored alunium, Gavl's works as well , just more trouble / etching/ prep work , etc , for the painters. The big box guys have both, I think , not where I shop for metal but IIRC I've seen it in Home Despot.

On that drawing maybe just a little seperation showing the building wrap / or felt over the "Z" metal , I know thats hard to show and I think you have it right but if it's hard for me to be sure , someone who doesn't know what they are looking at might not catch that little detail. And thats the devil of it , "Think like rain" , lead it out / on top of / going away from the building/ to day light.

MountainDon · September 05, 2007, 11:45:30 PM

Thanks.

There's a local metal roofing specialist that sells wholesale $$ to anyone with money and the ability to find his place of business in the out of the way in the run down industrial end of town. He's got everything a fellow, or gal, needs metal-wise for building.

I found out about him from the guys who did my house metal roof.Pays to chat with them.

I'll get the eraser out and redo that detail. The devil's in the details.

[edit]changed the drawing[/edit]

September 05, 2007, 11:53:26 PM

Beauty of an explanation there, guys.

MarkAndDebbie · September 06, 2007, 05:00:30 AM

Vinyl flashing OK there PEG? Anywhere you wouldn't use it?

PEG688 · September 06, 2007, 08:36:14 AM

I've never used vinyl flashing , it may not be around here. I've used a vinyl like jamb sill flashing before , how thick is this vinyl flashing your wanting to use?

As far as where I might not use a vinyl product IF it where readily avaiable , I'd think I'd not use it when pouring saya cement stairway or side walk / ram up against the house / rim joist. I'd wonder how the chem . in the mud might effect it. Metal does ok , used it and have removed metal from behind concrete after many years of use finding it in goos shape / stil doing the job it was put there for.

MarkAndDebbie · September 07, 2007, 05:00:27 AM

QuoteI've never used vinyl flashing , it may not be around here. I've used a vinyl like jamb sill flashing before , how thick is this vinyl flashing your wanting to use?

As far as where I might not use a vinyl product IF it where readily avaiable , I'd think I'd not use it when pouring saya cement stairway or side walk / ram up against the house / rim joist. I'd wonder how the chem . in the mud might effect it. Metal does ok , used it and have removed metal from behind concrete after many years of use finding it in goos shape / stil doing the job it was put there for.

It says it's .015 gauge. I started looking at it when I was looking for a termite shield. They stock it here at the building supplies as well as HD. It reason I was looking was it doesn't react with the ACQ. I think John C mentioned it when I was asking about the termite shield.

Here is a link http://www.duraflash.net

Thanks.

PEG688 · September 07, 2007, 08:45:52 AM

Quotehttp://www.duraflash.net[/url]

Good point that ACQ $hit is really a PITA. Big mistake IMO , knee jerk reaction to the CCA issue in playgrounds, which really was solved with composites like Trex beening made in thicker sizes.

MountainDon · September 07, 2007, 09:08:59 AM

I found it a my local Home Depot. White and tan colors, different widths and roll lengths lus a ledger board type (they were out of stock on it)