Tyvek overlap with replacing siding one wall at a time

Numb · 06-11-2010, 03:12 PM

I have a 1 story house in central Texas, built in 83, brick on the front, and T1-11 on the rest. The T1-11 isn't in great shape, and I'm planning on replacing it with Tyvek and Hardiplank. I'm going to be installing the siding myself, and to keep the job manageable, I had planning on doing 1 wall at a time. The problem I'm running into is, according to the info I have found, the Tyvek should overlap 12" around corners. If I'm only pulling off 1 wall of siding at a time, it doesn't seem like I would be able to achieve the desired overlap at the corners.

Is there a good way to do this? Should I just strip all the siding off, wrap the whole house, and then put siding up as time allows? That idea concerns me because I know you can't leave Tyvek unprotected for too long, plus there's the risk of the wind or my dogs tearing it up. Any suggestions would be appreciated.

**kwikfishron** · 06-11-2010, 03:26 PM

Just run the Tyvek a foot long on each end. Wrap around and tack to the old siding until your ready to do the next wall.

Nail a couple of firing strips to it so the staples won’t rip out.

Numb · 06-11-2010, 03:39 PM

Quote:

Originally Posted by kwikfishron

Just run the Tyvek a foot long on each end. Wrap around and tack to the old siding until your ready to do the next wall.

Nail a couple of firing strips to it so the staples won’t rip out.

Thanks for the reply. Running it a foot long would give me overlap on one wall, but not the other. As I understand it, the wrap on each face is supposed to overlap the adjascent wall by 12", which means you would have a double layer at every corner. Is that not the case?

I've also been seeing a lot of support for using 30# felt instead of Tyvek. I'm not opposed to doing that... is the installation exactly the same, in terms of overlap, corners, windows, etc?

**kwikfishron** · 06-11-2010, 04:19 PM

30lb. Felt is all I’ll use. I have issues with Tyvek, in wet climates anyway. Probably not a issue in Texas.

But yes, you always want to wrap the corner. I fold a felt corner (inside or out) and install in one piece vertically then paper the wall horizontally. The corner ends up with double felt.

Numb · 06-11-2010, 05:16 PM

Quote:

Originally Posted by kwikfishron

30lb. Felt is all I’ll use. I have issues with Tyvek, in wet climates anyway. Probably not a issue in Texas.

But yes, you always want to wrap the corner. I fold a felt corner (inside or out) and install in one piece vertically then paper the wall horizontally. The corner ends up with double felt.

So you can wrap the corner with something like a 24" wide vertical strip, and then overlap the horizontal rows of felt that run down the wall so that they end right at the corner? If that's correct, then to do one wall at a time, I would first attach half of the vertical strip of felt, then cover the wall with the horizontal rows. When it was time to do the adjacent wall, I would fold the vertical strip over, and then do the horizontal felt down that wall. Let me know if I have any of that wrong. The part I'm unsure about is terminating pieces of felt right at the corner.

I attached quick drawing to see if I'm understanding it correctly.

Also, is it necessary to tape vertical seams of felt like you do with Tyvek?

**kwikfishron** · 06-11-2010, 05:35 PM

You got it.

Except with felt I cut the 3’ wide felt down the middle, then fold the 18” piece in half leaving 9” around the corner, so I get two corners out of one piece.

But you certainly can go wider.

No tape needed for felt.

Numb · 06-11-2010, 05:42 PM

Excellent. Thanks for the help.

**Gary in WA** · 06-11-2010, 11:00 PM

Yikes! And don't forget when you remove the T1-11 siding (that is also your sheathing to prevent racking and transmit wind, seismic forces) to install steel diagonal bracing at every corner and every 25' of wall.
http://www.strongtie.com/products/co...c-twb-rcwb.asp

Be safe, Gary

Scuba_Dave · 06-11-2010, 11:30 PM

No sheathing ? Are the walls insulated ?
I've found that sheathing helps seal the wall cavities, less air movement
Siding usually isn't replaced for 15-25 years
During that time the Tyvek/felt will be the only thing keeping bugs from the walls
Make sure you do the bracing

jklingel · 06-12-2010, 12:11 AM

There are special caulks used w/ Tyvek, too. Taping and caulking is recommended on Tyv. You can leave Tyvek, I've read, for 6 months. That said, I see buildings year after year w/ Tyvek on them; don't know if the Ty starts to deteriorate or clog up, though. I don't know about caulking felt paper, but it is good stuff for walls and I don't see how vertical caulking at the corners could hurt.

**kwikfishron** · 06-12-2010, 11:18 AM

GBR in WA Yikes! And don't forget when you remove the T1-11 siding (that is also your sheathing to prevent racking and transmit wind, seismic forces) to install steel diagonal bracing at every corner and every 25' of wall.
http://www.strongtie.com/products/co...c-twb-rcwb.asp

T1-11 is not necessarily "also the sheathing". It is not shown that way in his drawing.

Scuba_Dave No sheathing ? Are the walls insulated ?
I've found that sheathing helps seal the wall cavities, less air movement
Siding usually isn't replaced for 15-25 years
During that time the Tyvek/felt will be the only thing keeping bugs from the walls
Make sure you do the bracing.

1983 was 27 years ago.

**Gary in WA** · 06-12-2010, 03:03 PM

Since I started building houses since '73, I have never installed sheathing under T1-11. Most builders, here at least, used the T1 because it also acts as sheathing. Two for the money of one...... The added unnecessary cost would have to pass on to the buyer from the builder, which would undermine the sale. Since it was original, I doubt he has sheathing......

Behind brick or under Hardi or cedar lap, yes. Metal bracing with foam board, 1/4" foiled cardboard, let-in 1x4's, diagonal 2x4's, and flat steel strapping are substitutes for sheathing, if allowed by local Inspectors.

Be safe, Gary

Tom Struble · 06-12-2010, 04:34 PM

t111 is used as a sheathing around here to but only on sheds and some garages and barns,anything with conditioned space is sheathed then the panel is applied,which imo is the right way to use it

jklingel · 06-12-2010, 05:46 PM

Not knowing any better, we sheathed w/ 5/8" T1-11 in 1980. No problems, and we have frequent (very minor.... knock on wood) earthquakes. Had I known better, I would surely have used steel straps underneath the T. They are cheap, fast, and apparently work, so why not? j

Numb · 06-12-2010, 06:18 PM

I assumed there was sheathing under the T1-11, but I don't know for sure. If there is not, do I use the straps just while the house is exposed, or do I leave them on and install the felt and hardiplank over them?

As, is it practical to install sheathing if there is none currently, or would that lead to clearance problems with doors and windows?