Spray foam insulating joists in basement?

[peethree]

Hi, I have received a quote for upgrading insulation in my home (I am a limited DIY-er and this is not something I plan to do myself)

House is 19 yrs old, 2 story brick structure approx. 3100 sq ft, unfinished basement near Toronto, ON

We have no plans to finish the basement in the next 4-5 years. There is currently yellow batt insulation framed in halfway down the walls.

The contractor is recommending that we insulate only the basement "headers" (his terminology) with 2 component spray foam insulation. He will then cover the foam with R12 fibre glass batts and install vapour barriers onto the headers.

To clarify, this is the area at the very top of the basement walls, in between each joist supporting my main floor, all the way around the full perimeter of the basement

He says this will make far more difference then finishing the insulation down the other half of the walls.

Can I please get some additional opinions on this?

Thanks in advance,
Peeth.

['Andyman]

peethree,

I can't imagine why he wants to spray foam AND use batt insulation. Unless you can feel drafts at the sill plate where the joists sit. If so, this could be caulked and then the R12 batts could be placed between the joists. Doing it this way, any DIYer could do it. I have batt insulation in mine. As far as taking the existing wall insulation down to the floor, there is no great need for that as the building code requirement only calls for insulation down to the frost line in the ground outside. Should you finish your basement, it is worth the extra to add the extra insulation and of course, a floor to joist vapour barrier

[peethree]

Hi Andyman

Thanks for your reply. There is already yellow batt insulation there - he was going to remove it, then do his thing with the foam and new batt....hence my puzzlement.

See, where this all began is that we have had really high energy bills and wanted to look at ways to conserve energy...esp. since I work at home so our energy use is higher than the average bear anyway.

I had an EnerGuide for Houses audit done and they recommended several improvements, including:

Attic: current = R15, increase to R50 to save 6% on energy costs (I've since heard from several sources that you need not go above R40 - so I'm getting quotes for blown-in cellulose to get me up to R40)

Basement: current = R1, increase to R20 to save 12% - having a heck of a time finding someone to even call me back about installing insulation - I guess everyone is so busy with new home construction
- and then this fellow said don't bother insulating down the walls, just do the top as per my original post

Space heating: current low efficiency, change gas heater to high efficiency to save 30%

...and then misc. things like caulking, etc.

I'm starting to wonder, should I just skip the basement and focus on my attic and getting a new heater, caulking etc., then worry about insulating my basement further when we get around to actually doing any finishing / renos in the basement?

And how can I tell what the R-value of the current batt is? (I suspect we got an R1 rating because the basement walls are only half finished)

Thanks again
Peeth

['Andyman]

peethree,

Not a bad idea to start at the attic as that could be the biggest source of heat loss. Blowing in is obviously the fastest way to go, but depending on the estimate, and if you are reasonably fit and nimble, batt insulation comes precut to fit in between joists and it is just a matter of getting up there and laying it in place. Just dont compress it as it loses it's efficiency. The batts are marked on the paper backing with the R value. Caulking where necessary is also a big plus for energy conservation. Replace the batts at the basement joists also for a greater R value. Even switch plates and receptacle covers on outside walls can be fitted with small gaskets behind as sometimes a draft can originate there also. I cant comment on the space heater as I've never used one. No question, good insulation, caulking, have kept my bills surprisingly bearable in a somewhat smaller 2400 sq. ft. house.

[peethree]

Hi Andyman,

Thanks again! We'll continue with our homework and also look at doing the attic ourselves.

(quote)Caulking where necessary is also a big plus for energy conservation.
-- yup, I've started that already and am making my way through the house inside and out. Next up is weatherstripping!

(quote)Even switch plates and receptacle covers on outside walls can be fitted with small gaskets behind as sometimes a draft can originate there also.
-- yup, already have done that too (including plug covers for the unused outlets)

(quote) I cant comment on the space heater as I've never used one.
--sorry, that's the Energuide terminology - it's referring to the furnace

I also have found that putting plastic film on some of my windows during the winter months can really make a difference and would recommend this to other readers - it's not that hard to do (even an amateur DIY'er like me!)

Thanks again for all your help!
Peeth

[spotofbother2]

Could someone tell me the difference between icynene and icylene. they are both listed in the yellow pages in my area.

I have a fieldstone unfinished basement. Can it be insulated by simply applying spray insulation to the surface? What preparation is required?

[adriand]

Hi

I'm planning to do the spray foam insulation in the headers as well. I do notice a lot of drafts coming through the sill plate area in the winter.

I have existing batt insulation in the cavities but its clear that spray foam would do a much better job of sealing every point of entry . Especially where the headers are parallel to the foundation wall. This space would be easy to fill with spray foam.

As for the roof insulation, make sure the contractor puts "morvents" or similiar on the underside of the roof decking. These vents prevent the new cellulose insulation from blocking the passage of air at the eaves and preserve your ventilation. This is important to prevent moisture buildup in the roof.

Make sure your bathroom vents are hooked up to roof vents with metal duct too before you put the cellulose. Once its in you wont be able to access anything in the roof area easily. You dont want mould growing up there.