Old Cypress Home w/ No Insulation
Location: New Orleans
Construction: on Piers, Dutch Lap Old Growth Cypress, Felt, Studs, Drywall (No Insulation)
I recently had spray foam insulation applied to the roof, totally encasing the rafters. When I finish working under the house, they will come back and foam the floor.
I am going to replace all of the old leaky windows. I have chosen a window that has the “J” channel built into the window unit, so that it is completely sealed.
I am going to use fiber cement siding to re-side the house. Here is where the questions come in.
Since the house has Dutch Lap siding, it leaves a nice flat surface unlike regular lap boards. Can I keep that and just nail the sheathing directly to it? If I can, then I wrap the house and install the windows and window flashing. Then I put the siding and joint flashing, will I still need to insulate the walls?
I really don’t want to tear the old siding off if I don’t need to.
Thanks for the help.
Replies
OK, I'll bite.
I am from the north, so I am not qualified one bit to offer advice.
Does it get hot in N.O.? Would insulation in the walls help along with what you have already done? Would it help enough to spen money doing it?
If yes, then what's the thought about drilling holes in your existing siding and blowing insulation in the stud cavities?
Is there a fear of mold growth or some other problem?
Would it be better to let the house "breath"?
I wonder if you went over to the Building Science website and perused around for a location specific answer?
I will contact someone from your state and ask them to stop by here and offer an opinion, which might go on to help you.
Best of luck.
Typhon,
I'm 2 hours north of you so I'm familar with the house type and climate. I would get the walls blown with cellulose before I did the house wrap and siding. Insulators will drill holes at the top of each stud bay, blow the cells and plug the hole. Pay attention to nailing patterns on the old siding to spot diagonal bracing. Make sure that the bottom of the walls are closed up if it is balloon framed. Payback will be quick. Will also decrease the sound of gunfire. :)
You can order your windows with jam extenions or make your own.
KK
Thanks
Do they only drill the one hole? Here we've had a couple jobs where they used blown fibreglas and drilled a couple-one to let the air escape while filling and also to enable them to not have to fill the whole cavity from up top. Maybe that was just a fibreglas thing?
Calvin,
I've only seen them do one hole per bay but that was cells. We pulled some siding in places to check and everywhere was full. Seems to be a good system.
I guess with the next flood Typhon's house is going to float with the foam under the floor.
Did you see the get together in your neck of the woods at BTC?
KK
Yes, thanks.
Columbus and I'll keep an eye out for what day. Might be possible-couple hours and a bit to the north side.
Cripes, that'd make a full day of it ..............
I used to renovate houses in New Orleans. First, why in the world do you want to cover up the old growth cypress siding??? That is great stuff. My parents had it on their house that got three feet of Katrina water and it came through fine, once they scrubbed off the water line (like on a boat).
I would keep the siding and avoid all the extra expense of the cement board.
Spray foam in the attic is good.
Spray foam in the walls would be good if you can afford it. Otherwise think about Spider chopped fiberglass dense-packed in the walls. It won't grow mold which is a consideration in the NOLA climate.
Under the house I suggest you use polyiso foam panels instead of spray foam. Even better if you can find XPS foam panels treated with borates. There is a real risk of termites (inclusing Formosan termites) tunneling in the spray foam under the house. The foam panels would be attached under the floor joists giving you room for the wiring and plumbing under the floor, and making it simpler to gain access to do repair work later. First air seal the floor penetrations with spray foam...
Good luck!
Billy
Re:
Billy wrote:
I used to renovate houses in New Orleans. First, why in the world do you want to cover up the old growth cypress siding??? That is great stuff. problem is: i have to keep painting it every 5 years. at $10k a pop, it's getting expensive to keep paint on the place. a friend of mine has had the hardie siding for 10 yrs. now with the original paint and it looks great.
My parents had it on their house that got three feet of Katrina water and it came through fine, once they scrubbed off the water line (like on a boat).
I would keep the siding and avoid all the extra expense of the cement board. actually, i got a quote of $12k to do the siding. that's not much more than one paint job.
Spray foam in the attic is good. yeah. i'm liking it already. the temp in the attic is the same as in the house and it's a lot less dusty around here.
Spray foam in the walls would be good if you can afford it. Otherwise think about Spider chopped fiberglass dense-packed in the walls. It won't grow mold which is a consideration in the NOLA climate.
Under the house I suggest you use polyiso foam panels instead of spray foam. Even better if you can find XPS foam panels treated with borates. There is a real risk of termites (inclusing Formosan termites) tunneling in the spray foam under the house. The foam panels would be attached under the floor joists giving you room for the wiring and plumbing under the floor, and making it simpler to gain access to do repair work later. First air seal the floor penetrations with spray foam...sounds like a definite option to consider. i had forgotten about the termite issue. i have been lucky with them so far. i guess it also helps that a friend of mine had a 55 gallon drum of clordane and he used to spray my house for free. it has been a long time since it was treated with it, but i haven't even seen a termite around here. or a stray cat or dog or squirell either for that matter : ) i don't think you can get that stuff anymore, but it really seems to have worked well all these years.
Good luck!
Billy
Hey typhon,
You're right about the paint issue. That's a very tough climate for paint jobs lasting and mold on the paint. Part of me still hates to see you cover up the cypress. I would think someone might remove the siding to re-use it and PAY you in the process.
The chlordane works wonders with termites. I wonder how much chlordane and DDT we ingested crawing under houses in NOLA?
My brother lived in an apartment in the French Quarter where the pest control people came in and sprayed some chlordane or DDT (after it was banned) and it sent him to the hospital. As kids when DDT was still legal I remember running behind the mosquito fogging trucks... that probably explains a lot about me... LOL
It is worth buying some Boracare and spraying it on the wood and sheathing around window openings and under the house on your floor joists, sills, etc. before you put foam underneath. It is non-toxic to humans but toxic to termites, gets absorbed deeep into the wood, and you can paint/foam over it, but it is water soluble so it cannot be exposed to the weather. It is cheap insurance if you are going to live there for a while.
I'm sure you're eating King Cakes and getting ready for Mardi Gras about now...
Billy
Yo!
You wanted response, well-you got it.
You still within ear shot? This isn't a chatroom, answers come thankfully when someone has something real to say.........
along with a little BS'ing along the way.
Hey Calvin,
I haven't been here in a long time. The "new" Breaktime forum still sucks. They really ruined it here. I still can't figure out how to follow all the replies but I'm not sure it's worth the time to learn.
Billy
Billy
If you're speaking of these changes that are currently being made here, well-jury is out.
I may have gotten used to it, so I'm a poor judge. However, I've found it workable. Hang around if you like, best of luck if you don't.
Hell, spring training is just around the corner. All is well.