Q&A: A Forum for Lakesideca Experts and Beginners

Q & A Instructions

[Click map to enlarge]

The GBAGreenBuildingAdvisor.com web site has a wealth of articles on a wide variety of construction topics. Before posting your question, you may want to check out the articles on this page: How To Do Everything. You just might discover an article there that provides the information you seek.

Please register for a free account or sign in to ask and answer green building questions.

If you want to post a question, the usual rules of courtesy apply:
1. Be nice.
2. If you can't be nice, be polite.
3. If you can't be nice or polite — well, please be brief.

To attach a photo or illustration: Under the box labeled “More explanation,” look for the words “File attachments.” Click that, and you should be able to attach a photo.

Thanks for joining the conversation!

6 Answers

Insulation on a gutted house


In Energy efficiency and durability | Asked By gneuner | May 10 18
1 Answer

Split air-source heat pump using ground loop instead?

I'm scratching my head over this. Several companies offer air source air-to-water heat pumps that are split (indoor compressor unit with outdoor coil/fans). Would it be such a stretch for them to offer an indoor heat exchanger that used a ground loop as a heat source instead of the outdoor fan coil? This would essentially be a super efficient ground source heat pump, far more efficient than most traditional ground source heat pumps that do not offer modulating compressors.

In Mechanicals | Asked By Lance Peters | May 10 18
1 Answer

Can I frame over blanket insulation and vaper barrier in the basement and get proper Fire Blocking?

I would like to leave the insulation blanket and vaper barrier in place when I frame the walls in my basement. Is it permissible to frame out from the insulation and then place the horizontal fire blocking every 10 feet by just compressing the insulation with 2x lumber against the concrete?

In Building Code Questions | Asked By R. S2 | May 10 18
2 Answers

Vapor retarder/barrier in an insulated above-garage floor

CZ6A, Ottawa ON

Our build will have a bedroom that extends out above the un-insulated garage. The floor will be 14" deep I joists and will be dense packed with cellulose (R50-ish). I'm planning to use Intello on the interior walls as a vapor retarder.

Question: What should I do for a vapor retarder/barrier above the garage?

Do I use a vapor retarder on top (between the floor sheething and joists), underneath (between the joists and the garage ceiling drywall), or is a totally different approach necessary? Should I be using a vapor barrier instead, like 6 mil poly?

In Energy efficiency and durability | Asked By Lance Peters | May 10 18
2 Answers

Exterior doors - steel with magnetic weatherstrip?

We are planning a "pretty-good" house for Zone 4 (Virginia). We are shooting for R-25 walls (using Zip-R 1.5 for the thermal break), R-50 ceiling, and a blower door test of 2.0 ACH 50. The finish will be white trim inside and out, with six-panel doors and a traditional look.

The house has three 36" X 80" outswing exterior doors with a "nine-lite" in the upper half. It also has a 36" X 80" inswing door leading to the garage (no lite), and a 72" X 84" center-hinge inswing patio door (full lite). All the doors are well-sheltered by roof overhangs.

In Energy efficiency and durability | Asked By Mark Harrison | May 10 18
19 Answers

HRV / HVAC engineering help in Ontario

My building inspector came to do my HVAC rough-in inspection today. After he had ignored my e-mails and phone calls for 2 months, I gave up and just bought the Zehnder unit I wanted. The last thing he had said to me was he was "sure it would be fine", and he'd call me back in half an hour (which he never did, called him again and got another promise of a return phone call that never happened). So now he claims he sent an e-mail telling me the Zehnder didn't meet the Ontario building code, and needs a report from an engineer to allow it to pass.

In Mechanicals | Asked By Trevor Lambert | Apr 26 18
11 Answers

Pondering a ducted attic minisplit air handler to replace the bedroom wall units

Hey everybody, we had an old cat infested 1200sf house in the Boston area gut renovated and have been heating and cooling exclusively with a multi-zone Mitsubishi mini split system, and while it has generally been working well, after two winters and one summer I'm thinking of making some changes. Hoping you can guide me through it.

In Mechanicals | Asked By User-6986065 | May 8 18
1 Answer

Air sealing options


I'm doing a double stud wall in VT - and am looking into air sealing options.

I have seen people use spray foam around windows and edges and that seems great, but also really expensive for the purpose.

I've read a little about kanuf ecoseal, but that seems a pro-line product, and not something that is easily obtainable.

What are some other options available? Would Prosoco Spray Wrap MVP be something that could be used in a similar fashion (seems I can order that).

Any other suggestions?

In Energy efficiency and durability | Asked By caryfitzhugh | May 10 18
38 Answers

How am I doing?

I just finished the first two weeks of monitoring my water heater. It looks like we're averaging ~5.5kWh/day. There's two adults showering twice a day, and two elementary school aged kids showering every few days. The dishwasher runs about 8-9 times per week. My rough estimates puts us at around an average of 20 gallons of hot water per day.

Can anyone chime in with their usage and family makeup so I can get an idea of home we're doing?


In General questions | Asked By Calum Wilde | May 2 18
6 Answers

The $700 question

I want to beat a dead horse just a little bit more. The horse's name is "Sill Sealer." In our soon to be built house, the difference in cost of materials for sealing the 2x8 plate with the standard pink or blue foam vs. a 7 1/4" x 1/2" Denarco Sill Seal is $700. Is it worth it? Is there a reasonably priced alternative I am missing? I have looked at Protecto Wrap and Weatherbloc products and neither has a 7 1/4" version, though Protecto will custom make one($$$$).

In Energy efficiency and durability | Asked By Kevin Spellman | May 9 18
Register for a free account and join the conversation

Get a free account and join the conversation!
Become a GBA PRO!