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13 Answers

Trusses and ceiling insulation and air infiltration elimination

Hello. We are building a new home at this time, and I am trying to maintain a Passive Haus standard. We are using ICF walls which will be easy to ensure an appropriate R-Value and infiltration value, but we are also using trusses. I would like to use cellulose totaling to about R-60 or more in the ceiling. I just am not sure of the best way to seal the truss overhang and ensure close to zero air infiltration in this situation. Please advise on good techniques on sealing the trusses.

thanks much.

In PassivHaus | Asked By Mark Dickerson | Mar 27 11
6 Answers

Ipe vs. Ipanema decking

Do you know the pros and cons of natural, just presealed ipe vs. stained Ipanema decking?
Need to decide what to use on our front deck.
Thank you!

In Green products and materials | Asked By Karen Miller | Mar 28 11
3 Answers

XPS/Cellulose Remodel in Winnipeg - HELP please! :)

Hi everyone,

I've read a LOT of threads here and I'm actually overwhelmed. I have 10 tabs of GreenBuildingAdvisor open and I feel like my brain is going to explode. So I am just going to ask... Thanks in advance for reading my post.

First off, I've seen Riversong and JKLingel, Gary Bergeron, Martin Holladay, and Peter Yost making lots of awesome posts and articles on this site; and I've been awed by the stuff Joseph Lstiburek has over at BSC. Thank you all tremendously for your dedication!

In Energy efficiency and durability | Asked By Danny Vanderbyl | Mar 28 11
4 Answers

best place online to buy FSC IPE

We are looking for the best place to buy FSC Online, natural with just sealer and the side click attachments. Also, any recommendations on the type of IPE to get. Our front porch is on the Southwest side of our house, so will get a lot of sun (we live in Massachusetts). Thank you! - Karen

In Green products and materials | Asked By Karen Miller | Mar 28 11
5 Answers

Exterior 1920's block/brick wall that must be insulated — but HOW?

I have a headache that have been researching as I need an affordable fix to be completed by the end of this summer.

Here is the deal: the 27'x70' wall in a zone 5A (on top of a mountain to boot) you see in the attached pictures used to be the interior wall of a building that has been torn down. I now own both lots, our building does not use this wall for support, but it is used as an exterior wall. The metal plates you see are tying this wall into our steel I-beams and presents a good bit of thermal bridging.

In Energy efficiency and durability | Asked By John Trembly | Mar 27 11
1 Answer

Which is best PEX for new construction?

If we go with PEX, which is the best one for our plumber to get? Can you recommend one that is BPA-free? And any other things I should note?

Sorry -- reposting from my incorrect previous question.
Thank you,
- Karen

In Green products and materials | Asked By Karen Miller | Mar 26 11
8 Answers

Open-cell foam against rafters?

I live in Connecticut and recently had a home energy audit, and the main issue they found is that my attic is not insulated enough. My attic floor is insulated [not enough] and covered in plywood as we use it for storage. It also contains an air blower for forced hot air [hot water comes from boiler in basement] and AC.

In Energy efficiency and durability | Asked By Frank Perkins | Mar 26 11
2 Answers

Polyiso sheathing

Most if not all references to polyiso sheathing on here seem to be towards the foil-faced variety as opposed to felt covered typically used in roofing. I'm curious: why? Is it because of the foil helping with radiation, tape sticking better, or what? Both types have the same insulating values/permeance, or no?

I was hoping to use it on my exterior walls, over the existing 1" XPS, or is this a bad idea?

In Energy efficiency and durability | Asked By Aaron Vander Meulen | Mar 26 11
4 Answers

I'm a builder planning my first conditioned attic and have questions and concerns.

1. We build slab on grade. Any problems placing sealed combustion furnaces (Carrier) and water heaters (Navien) in the conditioned space? My concern is that I assume they are at least somewhat leaky (CO, CO2, etc.). If so, does that pose a problem to IAQ?

In Mechanicals | Asked By James Fincher | Feb 23 10
3 Answers

How do I air-seal the crack around a chimney?

What are the best ways to seal either a Metalbestos-type or a masonry chimney as it penetrates the air/vapor barrier in a ceiling?

In General questions | Asked By Jack Woolfe | Mar 26 11
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