Need some advice on an exterior procedure. How do you fasten the rigid foam to the studs? Adhesive or nails? Also, what works best to cut rigid foam?
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Here's the picture. Helping an older friend with his 3 story apt. building. It seems that the temp. inside is the same as the outside. 100 deg. summer, -30 deg. wimter. Well close to that. Removed some of the metal siding. then came tar paper, then 3/4" white foam board , then 2x4 studs with 3 1/2" r 11 fiberglass batt. Don't ask me what is holding that 3 story place up. Wants to replace sliding patio doors (which will bring up another thread as I do 99% interior work). Wants to replace the fiberglass batt. with extru foam board( the first 10' ), then put up the 3/4" extru foam board, housewrap, then siding. He does not want to change all the windows out , so dosen't want to change the 3/4" jam extension. If you nail the foam board up, it seems that everytime you miss, you will put a hole in the foam ? Flashing the patio doors dosen't look fun.
JRnBJ is kinda correct, but a generic answer would be nails or adhesive or both. You can use anything from a utility knife to a circular saw to a sawzall. Actually, a drywall jab saw works really well. It all depends on the thickness and how nice the cut needs to be.
I get paid to do carpentry. That makes me a professional.
If I work on my own house does that make me a DIY?
A circular saw sounds great. thanks
what goes on over the foam ?
if you are going to cover with a plywood nail base.. then all you need are a couple of long roofing nails.. the plywood is what really holds it..
however... your racking strength is gone.. because the plywood is not in contact with the studs.. most times there is no way to REALLY comply with the building code for racking strength unless you put the foam on top of the plywood
anyways... IF you are going to use foam panels .. think about putting them on the inside of the wall
also.. the only foam i will use in a house has to be BORATE treated , like PerformGuard... foam panels become a wonderful nesting area for vermin.. especially carpenter ants
I just finished applying rigid foam while re-siding a portion of my house. I applied polyisocyauranate over the plywood sheathing with a few roofing nails for temporary holding, screwed vertical strapping on over that (square drive deck screws) at stud locations, then nailed fiber cement clapboards to the strapping. Laborious, to be sure, and feasible primarily because I'm also replacing windows as I go (flanges nailed to the strapping, drywall returns for extra thickness on interior).
Buildingscience.com offers some great info about the choice between applying foam on exterior vs interior, and considerations specific to your climate: http://buildingscience.com/resources/walls/insulation_sheathings.pdf
g.... bldg science apparently performs a great service.. but sometimes i have my doubts about their overall strategies and the ultimate repercussions
i think they still tend to the ivory tower theoretical , rather than down in the trenches practical
in that whole 13 page treatise you linked to, there is not one mention of vermin in foam.. and i'm not talking about mold..
all of my experiences show that untreated foam harbors, conceals and encourages vermin..
that has to be part of the equationMike Smith Rhode Island : Design / Build / Repair / Restore
Mike, I am concerned. I bought POLYISO from a roofing wholesaler. Now is there a chance that it was treated? If they knew of the potential for invasion of "vermin", or would it be a buyer beware situ.?
Being as I am sidewalling most of it, I am paying attn.
The stuff I have has a grey/black fiberglass type outer layers or skin. 2'' is supposed to net an R 12.6 IIRC.
I already chlordaned the area ( I know, dont tell)..but I really wanted to acertain what situ you observed this "vermin" in, being as, I only have one shot at this particular wall. Spheramid Enterprises Architectural Woodworks
You seen this?View Image Spheramid Enterprises Architectural Woodworks
duane...
my office has 1.5" of the same exact material on it ( pole building )... as far as i kow it's a polyiso.. which is the same stuff i found vermin in before.. the only differenence is the thick asphalt felt shell they use on the roofing product
but the vermin can burrow in from the edges
i'd spray all of the logs with the Boracare and cover it up.. hell, son.. you and i'll be long gone before they work their wya thru to the inside..
my own personal decision is to use the EPS PerformGuard in the future...
the R-value is about half the polyiso... but no vermin and about half the cost too
edit: that damn black roofing insulation stuff has got to be the ITCHIEST stuff we've EVER used... right up there with haying and Rockwool
Mike Smith Rhode Island : Design / Build / Repair / Restore
Edited 8/6/2005 2:58 pm ET by Mike Smith
Itchy? No quid there. I thought I might get foil faced.( I am a dreamer). I cut it all w/ a circ saw.
I have a stand of from the existing wall, about 1'', so i foamed it, I will use a PT or Rdwood water table, wiyh drip groove, below the starter for the Hardie. mebbe that'll slow em down. Bug wise.
This wall is applied OVER the logs, ( in places) and aligns w/ the addition ALMOST dead nuts.....so my new framing is 8" staggered studs for the insul and thermal break..wind up with a R 30 wall, and that helps w/ the loss everywhere else ( I hope).
4" @ 4.3 per, oughtta make up for some othe places if I have my facts straight.
Did I mention I am getting tired of this? Only 18 yrs to go for the goal of finito..
I just came to belive, that them old guys that worked on this, were real carpenters, we just play one on TV.
It is hard work.
Gotta a Therma -TRu to hang in an opening that don't exist, stud wise..now I pick a cardinal ( plumb, level, flat,co-planer or make believe)..the wires for the lights dictated where I hinge the door, and "future" additions ( right) dictate that..
" will it go round in circles"? Uh huh,..... Spheramid Enterprises Architectural Woodworks
Get rid of that 4 inch crawl space and yer be alright.
be down with snakes
A person with no sense of humor about themselves is fullashid
Don't make me pull a ...Too late..
"let's work together"
Together we'll standDivided we'll fallCome on now peopleLet's get on the ballAnd work togetherCome on, come onLet's work together(Now now people)Because together we will standEvery boy, every girl and manPeople, when things go wrongAs they sometimes willAnd the road you travelIt stays all uphillLet's work togetherCome on, come onLet's work togetherYou know together we will standEvery boy, girl, woman and manOh well now, two or three minutesTwo or three hoursWhat does it matter nowIn this life of oursLet's work togetherCome on, come onLet's work together(Now now people)Because together we will standEvery boy, every woman and manAhhh, come on now...Ahhh, come on, let's work together...Well now, make someone happyMake someone smileLet's all work togetherAnd make life worthwhileLet's work togetherCome on, come onLet's work together(Now now people)Because together we will standEvery boy, girl, woman and manOh well now, come on you peopleWalk hand in handLet's make this world of oursA good place to standAnd work togetherCome on, come onLet's work together(Now now people)Because together we will standEvery boy, girl, woman and manWell now together we will standEvery boy, girl, woman and man Spheramid Enterprises Architectural Woodworks
And you thought you could ignore balloon knot.
I read their cold climate book three times, when I put up my shop. ( not finished yet) It was a little hard to follow.
Housewrap will be going ever the foam as per reply above. There will not be any plywood.
The easiest way to cut foam is to score it with a utility knife (or even measure and score all at once by extending tape the proper length, holding the smart end (with the box) so that your thumb is against the edge of the foam panel and drag the tape along, holding it perpendicular to the edge and use the little end dealio of the tape to score the foam). Then just snap it like you would drywall.
Tube adhesive (make sure it's for foam--some will melt foam--and/or staples (pneumatic gun) or special foam nails with big plastic washers will hold it on. But as one poster said, I would apply it to the inside, since it can be a vapor barrier (if applied properly). If you put it on outside, the poster who said to use strapping made sense--that way there's an air space and any water that gets in can evaporate or run out.
edit: We would apply foam over window and door openings, then use a jab saw (or really any saw can be worked through it gradually) and cut three sides, then score and snap the fourth.
Edited 8/6/2005 8:44 am ET by Danno
If staples is the way to go. then that is whay I wiull do as I have a pnu stapler already. Just don't want to put too many holes in the 3/4" foam. thanks
Don't know if it's the recommended way, but when I was a framer, we used pneumatic gun with staples all the time to put up Styrofoam. It worked fine and was quick.