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1 Answer

Can we replace fiberglass insulation with XPS?


We have a 33 year old townhouse that has a brick exterior on top of wood frame. There is fiberglass insulation in the wood frame, but we have lots of air leakage.

Would there be a problem with replacing all of the fiberglass insulation with XPS rigid insulation or spray foam insulation? If we did, would the XPS and or spray foam be an adequate air and vapor barrier?

Our goal is to reduce the air leakage and heat loss/need for air conditioning.

Thanks . . .


Asked By Phil Troy | Jul 3 14
8 Answers

Efficient basement dehumidification – how to?

Our deep energy retrofit of a 112 year old masonry building in Chicago includes a basement unit (garden apartment). The old foundation walls always draw some moisture and for that reason are exposed on the inside so that they can dry out. That works fine during fall, winter and spring, when the ERV removes that excess moisture. During summer, however, that moisture starts building up and I have a really hard time to control it.

Asked By Marcus de la fleur | Jun 25 14
4 Answers

Anyone have experience with Aeroseal duct sealing?

I'm considering developing a magazine article on Aeroseal duct sealing. This is a process where registers and diffusers are sealed with plastic and a vinyl based sealant is blown into the ducts. The sealant collects around leaks until they are ultimately closed off. The big advantage is it can seal ducts that are inaccessible for conventional sealing methods.

Here's more:

Patrick McCombe
Fine Homebuilding Magazine

Asked By Patrick McCombe | Feb 26 14
8 Answers

EPS as continuous insulation in above-grade, rainscreen cavity walls

We are building a house in Toronto, Canada. By code we need interior poly, so our walls need to dry to the exterior. The assembly is:

5/8" GWB
6 mil poly (vapour retarder)
2x6 wood studs @ 24" o/c w. R22 Roxul in the stud bays
1/2" plywood sheathing
Tyvek (drainage plane / air barrier)
1" continuous rigid insulation
1x4 PT wood strapping (fastened through rigid)
marine grade plywood or painted hardie board panels as cladding

Asked By wendy wisbrun | Jun 24 14
6 Answers

Looking for someone to design/build an energy-efficient home in Maine

I've contacted a few energy-efficient home designers/builders in the Cumberland County, Maine area to design/build a home for my family but they are backlogged with work for 6 mos-1 yr.

Can someone make some recommendations of quality energy-efficient home designers near Cumberland County, Maine and also quality builders of energy-efficient homes near Cumberland County, Maine?

Asked By Eric Cyr | Jun 20 14
8 Answers

Confused on air and vapor barrier with vaulted ceiling

Hello, I've done a ton of reading here and in just general and I'm thoroughly confused on what I should do. I'm in the middle of building a two story addition off the back of my house in central Pennsylvania. I've used scissors trusses and have fully vented soffit with a ridge vent. I plan on using knotty pine 1x6 on the walls up to a chair rail and drywall to the ceiling and then the ceiling will be 1x6 knotty pine.

Asked By SCOTT KOONS | Jun 29 14
5 Answers

Transfer fans from hallway to bedrooms

I'm looking at a few different heating and cooling options for a (very) efficient two storey house with no basement. An option I like is using one ductless minisplit air handler per floor. Simple, inexpensive, fairly easy to size properly, pretty efficient.

Asked By Graham Fisher | Jul 1 14
4 Answers

Exterior finish at top of PWF basement?

The "Permanant Wood Foundations Design and Construction Guide" by the Southern Forest Products Association,shows and discusses a treated plywood "protection strip" at the top of the underground portion of a PWF basement. It's, discussed purpose is to protect the poly damp proofing material from UV and other hazards. I would like to carry my thin brick to below grade. I propose replacing the treated plywood with a layer of 30# felt, stainless mesh (lath) and cement plaster to which the thin brick is attached with "thin set". Are there problems or "issues" with this?

Asked By Jerry Liebler | Jul 1 14
7 Answers

What is the recommended method for insulating a cathedral ceiling in a moisture-laden home?

My split level home was built in the 60's with insulating practices of the the era. No moisture barrier under concrete basement floor. R-3 fiberglass batt, fiberboard sheathing.
After structuring for an open floor plan and removing all the old 2x6 ceiling joist I have to re-insulate as well as re-roof. I mention this because I have the opportunity to add neopor foam board to top of roof sheathing. Really can adapt to any recommendation for ceiling , but will have to live with leaky house for a while.
Appreciate any help, thank you.

Asked By cameron morris | Jul 1 14
6 Answers

2nd story addition heating

We're working on an addition to a 740sf 1940s home in Portland, OR - addition includes +300sf on main level and new 2nd floor (1300sf). The existing furnace is brand new high efficiency gas, but not enough capacity for the addition. The owners do not want to replace it since it is so new. We are in the process of value engineering to bring costs down, but need to evaluate how to heat the new 2nd floor. Cost is an issue, but could possibly persuade them on a good investment.
Insulation: R-49 flat ceilings/R-30 vaulted attic storage space, R-23 walls.

Asked By Miyeko Endy | Jun 26 14
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