I am working with a customer to install new windows and reside their house, which currently has T111 siding, with Hardiplank lap siding.
My plan (simplified) is to fur out the walls to plane in with the gables, because they overlap the walls, wrap with Jumbo Tex building paper and install Hardiplank.
The customers are talking with another siding contractor who says that they never side over T-111 and that they will tear it off before siding. Since I have never heard of this being done I am wondering if I am missing something of importance.
Anyone have any thoughts or experience as to why the existing T-111 should be removed before siding with Hardiplank?
Thanks
Replies
T111 has issues with water intrusion causing rot inside the walls because it's hard to flash properly. Other than that, no issues I can think of.
No reason to remove the T-111. It should make good sheathing.
Beat it to fit / Paint it to match
This is the way the contractor is making his bid different than yours. There is no reason that I can think of as t111 is plywood with grooves. Of course if any was bad or rotted, my opionon will change.
Thanks to all who responded.I couldn't come up with a good reason to tear off the T111 either. I will know more after the customers meet with the other siding company.If anyone else has any thoughts, please chime in.I am planning on replacing any rotten or defective T111 before residing.I was originally going to fur out the walls under the gables but then got to thinking I could just tear off the T111 siding on the gables and everything would then be on the same plane. I could then install Hardiplank siding over the gable studs. Any thoughts about going that route?
No sheathing on gable ends? I'd be a little nervous, I guess. But I'm not a structural expert w/ stuff like that.
T1-11 should be a good sheathing/shear panel. It's structurally rated. No reason to remove, really. IMO
Again, I don't know where in Oregon the job is, (if it is in Oregon), but, even if you accept that t-111 is a structural shear panel, that doesn't mean the structure as a whole is adequate.
Structures fail in seismic events mainly in three ways: racking, sliding, and overturning.
A shear panel (if adequate) will prevent racking, but not sliding or overturning. Any time I open up a wall on an un-retrofitted house in an EQ zone, I at least suggest HD's and usually new or additional AB's as well.
k
It seems everyone is echoing my own opinion as far as leaving the T111 siding in place. The house in question is a 1980 ranch style home in the Portland Metro area of Oregon. We do get the occasional small earthquakes. I could suggest to them to have some hold downs installed. I have installed plenty of them in new construction but never as a retrofit. I am guessing that is something an engineer has to sign off on. I am unfamiliar as to what AB's stand for. Please enlighten me.Thanks
AB's are anchor bolts. If the existing ones are too small < 5/8" or spaced too far for the strength of the concrete, then adding new ones is usually recommended. Also, if they're not galvanized, they are probably rusting, and should be replaced/ supplemented.
I don't know about Or., but in Ca. there is no code for retrofits, so you're not required to get engineer's stamps on retrofit work. It can be helpful if you don't understand the basics of the systems, but isn't required. Most western states have downloadable retrofit details, and Simpson puts out a brochure that spells out the basics.
A 1980 house may or may not have any of this already. But if you're about to put up fiber cement siding, this may be the last chance to have a look in there for 20 years or more.
k
Ahh. Anchor bolts. My mind was trying to go someplace way more complicated than that. Thanks for clearing that up.The house, I am almost certain, will have anchor bolts but they are probably 5/8's.I agree it will be the perfect time to do a seismic retrofit. I am going to bring that up on our next meeting.
And anything else that might want to be adressed before you seal that puppy up. Blow in some insulation, maybe, or run some dedicated lines for tech, etc. I assume a 29 yr. old house doesn't need to be re-wired.
I obviously wouldn't do a high-pressure scare-tactic hard-sell. I'd just point out that with the high quality materials and superior workmanship I'm providing, that wall will be closed up for a long time.
If they're going to want anything done in there for the next twenty years, now would be a good time (all else being equal, of course- they may not have the $ now; or might rather do it at a greater expense later if their BofA stock rebounds).
k
I think the county of los angeles has downloadable seismic details.
Sheathing exterior walls with plywood is a good idea. I'd check the nailing before you cover it.
Exterior sheathing really adds to shear strength of the walls. In earthquake country they are all sheathed. It's required.
People who haven't built that way just don't get it.
You're going to get rot no matter what you have underneath if it isn't flashed properly. Why would t-111 be any different?
Actually, you raise a good point- how does t-111 compare to struc. 1 for shear panel strength? Might be an argument for tearing it off and replacing with struc one if t-111 is a lot weaker.
How many plies is t-111 anyway, it's been a blessedly long time since I've seen it...
k
I haven't seen it for a long time as well. It's 5/16-3/8" thick as I remember. It's going to add something. It's better than nothing at all. And that is what the other contractor is suggesting.
There's a lot of homes out there with next to no shear in the walls at all.
The exterior walls in my house are brick. The south facing brick wall makes noise all the time from expanding and contracting in a continuos heating and cooling cycle.
If there ever is a seismic event here I'm running for the hills.
If the house is standing now, why would there be any doubt as to the structural integrity of the T-111?
Because it hasn't been hit by a 7.0 (yet)
k
OK, besides that. Is Oregon seismically active? I know they have a few old volcanos...
Yup. Especially the western part. They get an 8.0 every 300 years or so, and it's been, oh hey look at that... 300 years.
The volcanoes are the result of upwellings of molten rock from the pacific plate being forced under the north american plate. As the solid cool rock of the pacific plate gets forced deeper by the overriding north american plate, huge sections break off and are melted. The breaking off is earthquakes, and the melting causes volcanoes.
Although, in recent memory, Oregon doesn't have the activity of California or Washington. And for all I know, the OP's job is in Minnesota...
k
The T1-11 we use is 5/8" and comes with either 4", 8" or 12" ploughs. It is considered structural sheathing and finished siding all-in-one.
I would leave it as it is but replace any sections that appear questionable. If the bottom of a number of panels is rotten or punky I would rip regular 5/8" CDX a minimum of 12" and replace the bottoms in 8' sections. A decent coat of primer at the exposed bottom edge is good.
Before applying the siding you will need to flash the building just as if it were ordinary sheathing. You will be retrimming the windows and doors to compensate for the change in wall thickness.
Leaving the siding keeps the building from racking, especially if you live in a seismic or high wind zone. The only Hardie siding that is considered a structural panel is the 4x8 sheet, which is applied directly to the studs after housewrap.
My guess is there will be no original let-in bracing in this structure and I don't think the other contractor will even think of retrofitting. James Hardie does permit straight to the studs attachment of lap siding but....
If you needed to sink another nail or two in the boards you are SOL if just nailing to a stud wall. Hardie will also lay better with a smooth solid backing and you won't be forced to cut each and every piece to fall on a stud for nailing. This will also waste less material and make the job zip along.
So, it's 5/8 with 1/8" deep ploughs? effective depth 1/2"?
how many plies?
k
And now that my inner salesman is activated, op's profile is in Oregon.
If I was residing a building on the west coast, I'd encourage new AB's, HD's, etc... in addition to new shear walls. And insulation and wiring upgrades, if needed.
As long as you're messing with the envelope, might as well get in there good...
k