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6 Answers

Are can lights really that bad?

I've seen the articles extolling the evilness of can lights and I can't argue the old ones are really bad. But, would an airtight LED leak very much air? With an attic above you could pile a little extra cellulose above it to compensate for the 2-4" you lose for the light. Most of the articles use the old lights as an example but don't quantify how bad a modern airtight one would be.

In Green products and materials | Asked By Brad H | Oct 14 16
3 Answers

When can we expect the R410a phaseout and what will replace it?

So this happened: http://www.nytimes.com/2016/10/15/world/africa/kigali-deal-hfc-air-condi...

What's next? CO2 refrigerant? HFOs? How long before we see non-HFC refrigerant equipment on the market? I keep meaning to replace my gas furnace with a heat pump but now I'm thinking maybe I should wait…

In Mechanicals | Asked By Nate G | Oct 15 16
3 Answers

Insulating wall next to garage ceiling

I live in NJ and had an energy audit done last year but I found that two of my rooms still remained cold.

These are two bedrooms where half of the rooms are above a garage. The exterior walls of these two rooms have part of the walls with no sheathing (see photo one). This area is cold because the garage roof has soffit and ridge vents so there is cold air in the winter. dense pack cellulose was blown into the garage ceiling joists below these two rooms, but it is still cold near these exterior walls.

In Energy efficiency and durability | Asked By Max C | Oct 14 16
1 Answer

Prosoco Cat 5 vs. peel-and-stick tape

For exterior OSB joints. Is it better to use the Prosoco Joint Filler caulk/compound or just use peel & stick tape? Which will last longer?

Prosoco is supposedly breathable so it allows moisture to dry. Any feedback in the field?

In Green products and materials | Asked By Peter L | Oct 16 16
1 Answer

Detail for innie inswing door with thick exterior foam?

I'm planning a house for Rochester, NY, zone 5. The wall have 2x6 studs, 7/16 sheathing / air barrier, 4" rigid foam, a wrb, a 3/4" rainscreen, and 3/4" thick horizontal shiplap siding. The foundation is a monolithic slab on grade with 4" exterior rigid foam. The finished floor height is 2" above the slab. There are 4-7' overhangs over every exterior door.

My general question is, how do I install an innie, inswing exterior door in this assembly?

I want an inswing door because it can't be blocked by a snow drift.

Here are a few specific questions:

In Green building techniques | Asked By John Ranson | Oct 15 16
17 Answers

Options for replacing 2-cycle gas weedwhacker / string trimmer?

I recently replaced my gas-powered push lawnmower with a manual reel mower (Fiskars Staysharp Max Reel Mower, 18-Inch) for maintaining the grass on our small (7,500 sq ft) lot.

In Green products and materials | Asked By Robert Hallenbeck | Jun 26 16
2 Answers

Installing exterior trim with a rainscreen

I'm planning horizontal shiplap siding over 4" of foam with a rainscreen gap for my house. How do I make the rainscreen accommodate exterior trim around the windows? Do I just make the furring picture frame wider than the trim, wide enough to support the ends of the siding?


In Green building techniques | Asked By John Ranson | Oct 14 16
3 Answers

3/4" of XPS on a basement floor vs. 1½" in a Climate Zone 7 basement

A friend is planning a basement reno..

it has no insulation at all on the interior or exterior or under the slab. It was built in about 1995. The basement has about 18" above grade, the balance is underground. It has never had bulk water seep in and its unlikely that there is poly under the concrete as this wasn't commonplace here (Winnipeg Manitoba Canada).

He wants to add 3/4" XPS to the floor (1150 sq/ft) and cover that with either 5/8" or 3/4" t&G OSB or plywood using only the T&G joints to hold the sub floor together as a unified surface.

In General questions | Asked By Tim Brown | Oct 13 16
7 Answers

Radiant heat vs. split system heat pump

I have a 24 x 24 foot family room with a 16 foot cathedral ceiling. It's built over a garage. It has radiant heat running off an oil fired boiler (the rest of the house has radiant baseboard. The room has a split system heat pump that is used to provide AC. During the week the room only needs to be heated for a about 5 or 6 hours in the evening. Does it make more sense to keep the radiant at a lower temperature, say 65 and run the split system in the evening or run the radiant at a higher temperature. It typically takes several hours for the radiant to come up to temperature

In Energy efficiency and durability | Asked By Alex Ivkovic | Oct 11 16
2 Answers

Internal wall of a 1835 house


I live in a greek revival house built in 1835 on Cape Cod (MA). Over the years this house has gone through different renovations/updates some more successful than others. We are in the process of renovating the top floor which still has original wood windows (in really bad shape unfortunately) and no insulation.

The house uses post and beam construction (I was told) and the side walls (East and West facing) don't have any cavity. The North and South walls (front and back of the house) do have cavities and have been insulated with cellulose 3 years ago.

In Energy efficiency and durability | Asked By Riccardo La Rosa | Oct 14 16
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