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5 Answers

Ventilate dead space behind kneewalls

I have recently completed my attic renovation. We moved the insulation layer to the roof deck and brough our hvac inside the thermal envelope. We finished the space for an extra room.I now have keewalls on both sides of the room with a triangular space behind them with all the ducting/hvac etc. behind them. I did not provide any registers or returns to this dead space. Should I be concerned that there is no air movement or turnover in this space? I was thinking it might be wise to provide a louver through the kneewalls to allow some air movement.

In General questions | Asked By Rob McKenzie | Sep 19 12
2 Answers

Air Handler is a good option?

We are renovating an older 2 story home in the Hudson Valley NY (zone 5) We had a new high efficiency gas heating unit installed, and the installer recommends an air handler to distribute the heat on the 2 floor in lew of installing baseboard. The first floor already has baseboard heat.

This will be a rental, but a decent one I hope. His argument is that we could easily add air conditioning this way, and the cost is not that much different than the baseboard. We have a conditioned attic space to put the unit.

In Mechanicals | Asked By Nyle Phillips | Sep 22 12
8 Answers

What's so wrong about oversizing HVAC?

We're building a new home.

Yes, I've heard the advocates of right-sizing the A/C to keep the unit as small as possible. Take into account everything -- windows, ceiling ht, wall types (in our case, SIP with 6" foam, etc. Size system for max summer temps (in our case, 105 degrees a dozen or so days). etc. That way humidity is better controlled with a system that is constantly going during those maximum days.

In Energy efficiency and durability | Asked By Leonard Miller | Sep 20 12
2 Answers

Hardwood flooring

What specialized tool exists that can cut a groove into an unfinished hardwood floor board? Hand held router or is their a special blade that can be used on a table saw to cut out the groove?

In General questions | Asked By kevin haag | Sep 21 12
5 Answers

Looking for a NYC metro area fresh air systems contractor

I am in the process of buying a house, it closes next month. Its relatively new built in 2004 - but there aren't any special green features. I hope to change that gradually, starting with a fresh air system.

In Mechanicals | Asked By J M | Sep 21 12
10 Answers

Ultimate Air vs. Zehnder HRV

I recall seeing in the comments for the article discussing a new way to duct hrv's that one of the Zehnder reps was disparaging the Stirling Technologies Recoupaerator 200dx for having something to the effect of misleading, incorrect, etc. performance numbers and that it does not stack up to Zehnders products. I was wondering if that rep and anyone else could clarify why the Zehnder product would be better than the 200dx and how they differ in function? The cost of the 200dx is significantly less.

In Mechanicals | Asked By Spencer Burnfield | Sep 4 12
6 Answers

Installing 2 Vinyl windows with no nail flange in a 6" opening depth

I'm turning our sunroom into a finished space. The current slider windows are 2 be replaced by 2 vinyl single hung units (73" x 52"); each unit has a 2 single hungs and a vinyl joint between each to make it a solid unit.

The current sill is sloped 2x8. Based on my recommendations and manufactures install is to shim sill at 24" and jambs at 16" (only fastening the jambs).

They say if > 65" wide consider fastening through the still; but from the advice I've been given from contractor and rona is to not fasten on the sill as it could compromise drainage.

In General questions | Asked By Mike Tew | Sep 20 12
3 Answers

Hardwood installation

How does one correct for the the common area (hard wood) not being straight during installation now that I'm installing hard wood into the corresponding bedrooms?

In General questions | Asked By kevin haag | Sep 20 12
1 Answer

Substrate options for earthen plaster on interior over cellulose

I am building a home in coastal BC and discovered clay under our plentiful sand. It would be great to use this for an earthen plaster on the interior of our house. Currently, the plan is a staggered 2x4 stud wall on a 9.25" plate blown with cellulose. The exterior will have plywood, Typar, 2" rigid insulation such as Roxul ComfortBoard IS strapped (perhaps with pipe or wood squash blocks or just extra thick strapping direct on plywood and Roxul cut to fit between), so that there is a rain screen gap, then fiber cement siding.

In Green building techniques | Asked By Patrick Walshe | Sep 21 12
11 Answers

Fastening methods for Roxul ComfortBoard IS

I was wondering if anyone has field tested Albert Rooks' suggestion of using full thread (or broken thread) screws to get consistent screw compression on the strapping and prevent wavy siding. That sounds way simpler than cutting holes in Roxul / inserting sections of plastic pipe. One builder did not know about these options and ripped all the roxul off a side due to this issue. His Comfort Board was 1.5 inches thick I believe. I would like to put untreated strapping over 2" comfort board then fiber cement siding.

In Green products and materials | Asked By Patrick Walshe | Sep 17 12
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