I just bought my first home: a semi-detatched double brick home with plaster and lath walls. I want to insulate the exterior walls, the space is limited (its a downtown Toronto home) so I am debating if I should frame with 2×3’s or 2×4’s. Regardless I want to insulate with fiberglass batts and am curious if I can place the batts directly against the brick or if I have to put some sort of housewrap up first before I place the insulation? Any suggestions?
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I'm not sure that housewrap will do much good. The brick is a pretty decent wind barrier (especially the way they build brick homes in Toronto), and you don't need the housewrap as a rain shield.
Just pay attention to areas around windows, doors, etc, to caulk/seal tightly.
In your situation foam might be a better choice than fiberglass -- more R value per inch.
Dan, you're wasting your scarce bottom of the payscale dollars with FG batts.
Mike Smith's post, ESP and then build your wall will isolate the framing from the brick, thereby eliminating heat loss through the studs. If you do as he suggests you should be able to get an air tight wall with much better R value than you would achieve with FG batts.
It might cost more right now, but you won't be happy with the results you get from what you are planning now.
Joe H
Mike and Joe nailed it. FG is a waste of your money compaired to EPS and cellulose. Do a search and do it right, you will save money and be more comfortable in the long run.Garett
'Twasn't me.
People never lie so much as before an election, during a war, or after a hunt. --Otto von Bismarck
Yerrite, 'twasn'tthee.
Maybe who it were will see it nnyway.
Eitherway, FG ain't the way.
Joe H
Yeah, especially when you're trying to minimize thickness, FG isn't the optimal choice.For those who aren't familiar with Toronto, I'm guessing that the OP's house is like many I saw in older parts of of the city when I was frequenting there some years back. Basically, the houses look like small town bank buildings built ca 1900 -- solid red brick, flat roofs, sometimes even dentil/turret features along the roofline.
People never lie so much as before an election, during a war, or after a hunt. --Otto von Bismarck
Greetings Dio,
This post, in response to your question, will bump the thread through the 'recent discussion' listing again.
Perhaps it will catch someone's attention that can help you with specific advice, however in the event you fail to receive the information you desire, you might find it in the archives.
If you scroll up in the upper left corner of your screen there is an advanced search function that will take you to a page of instructions directing you to previous threads dealing with whatever you type in the search bar.
If you type in 'dense pack', 'foam insulation' or other keywords of the subject matter you'll get a supply of data from those old threads.
General concensus is fiberglass batt insulation is on the bottom half on the list of viable housing insulation.
I would love to pony up the dough and get the spray foam, but this is my first home, I'm getting married in the summer and well I'm a second year teacher at the bottom of the payscale. Needless to say I have a tight budget.
I pretty much have to go with batt insulation. Unless anyone has other suggestions to maximize my R-value. Remeber my space is limited, I can't frame with 2x6's. I'll probably frame with 2x3's.
In terms of batt insulation I have just seen Owen's cornings and Roxul's. Any recommendations as to which is better?
dio.... i'd use EPS foam against the brick... you can buy it in 1" x 2' x 8' sheets
http://www.r-control.com/performguard.asp
and.. i'd use a borate treated EPS.. it's fairly cheap
Perform-Guard.. then you won't wind up with termites and other vermin
inside that i'd build a 2x3 wall.. and insulate that with celluloseMike Smith Rhode Island : Design / Build / Repair / Restore
There used to be a system of foam panels with rabbeted edges and a rabbet down the center. You glue the panels up and then place 1x pieces into the rabbets and shoot them in place. Then screw drywall into the 1x pieces. Designed for basements, but probably ideal for this duty too.Not sure if it's still around, though, or generally available.
People never lie so much as before an election, during a war, or after a hunt. --Otto von Bismarck
http://www.dow.com/styrofoam/na/res-us/products/wallmate_slotted.htm
Yeah, that's the type of stuff I was thinking of. You can get R10 with two inches of the stuff, and there's essentially no thermal bridging.Dunno about the price, but you save on framing, etc.
People never lie so much as before an election, during a war, or after a hunt. --Otto von Bismarck
On the subject of fiberglass batt insulation, there have been a number of posts describing tests made where fiberglass batts decrease in insulation value as the outside temerature lower.
Perhaps someone might have a link to those posts.
In this case at least fiberglass wouldn't suffer from infiltration to the extent that it does in a standard frame structure. So you'd get a little closer to the theoretical R value.The other factor that affects FG R value is internal convection. The force driving convection is pretty much proportional to temperature gradient, so this is likely the effect that the tests are measuring. Using denser FG (either buying the dense stuff or, eg, compressing 5.5" batts into a 3.5" space) will reduce the convection problem to a degree.
People never lie so much as before an election, during a war, or after a hunt. --Otto von Bismarck
I have a question that is bit off thread , but perhaps relevant to some.
Many yrs ago I was told that the only foam to use in wet(ie.:underslab, underground, subsurface,or otherwise damp locations is Extruded Polystyrene or EPS (generally Dow Blue or Foamular pink), now I see and read "EPS" being applied to Expanded Polystyrene as the identifying name.
So two question, 1)how does one tell the difference between the two when writing or reading about them , and 2) Is there really a difference in performance in the listed applications.
My own empirical tests many yrs ago (dropping small samples of each , plus thermax, and any other kind of building foam I could find) , into a bucket of water and letting it sit for a week or so showed that indeed the Extruded was the only one that didn't absorb the water. I know that the best hot tub covers were made from the Extruded, I assume because of it's ability to handle the water vapor and wet conditions.
Expanded styrene foam is generally shorthanded as EPS, and is also known as beadboard. Extruded styrene foam is shorthanded as XEPS or XPS.The extruded stuff (XEPS) is a monolithic closed cell structure and has R-5 per inch of thickness. It will not absorb water, and is used for flotation on houseboats for this reason.The expanded stuff (EPS, or beadboard) is made up of many small beads of foam tightly compressed together. Although the individual beads are waterproof, the spaces between them can hold a lot of water. EPS has about R-4 per inch of thickness when dry, far less when waterlogged. EPS is a lot cheaper than XEPS, and works well where it will be dry in service. Humidity isn't a big problem, either. XEPS is called for where water will sit against the insulation, like below grade.Bill
Thanks, the "XEPS" shorthand isn't something I had seen before, clears it up for me.
Studies show that house wrap isn't much different than good old fashion tar paper. Just five cents more expensive.
Where are these studies?
People never lie so much as before an election, during a war, or after a hunt. --Otto von Bismarck
They were found with the Dead Sea manuscripts.
Mike and Joe are dead on for your climate.(in my humble opinion) Maybe you can rent the cell blower where you buy the material? Use a wet cell product and the starch/borate treatment in most of those products acts as a "glue" to hold it together as well as insect control. That way you wont have to buy a poly moisture barrier. Three good friends to help you and it shouldn't be too much of a problem. Mind your vents and electrical boxes, get behind your plumbing, and no beer til AFTER the job is done .you should be cool. This may help
http://www.codecollegenetwork.com/nc/insu.html
Muse
Sweet Georgia Brown!
You guys rock, I needed some advice and you guys delivered! Needless to say when I have anymore questions Breaktime will be the place I turn to. Seeing as I will be doing the bulk of the renovations myself I'll need all the help I can get.
Much obliged folks!
http://www.regalind.com/regal_wall.htm
damn, am I fat!