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12 Answers

Can I make mini splits more efficient at extreme temperatures?

I renovated a home in northern New Hampshire with meaningful air sealing and additional insulation. I installed Mitsubishi hyper heat mini splits upstairs and down, but have baseboard and wood stove backups for when the temperatures drop below 20f and the mini splits need help. Overall, I am happy.

My question is about the outdoor units. Below a certain outdoor temperature the mini splits lose some energy efficiency.

In Mechanicals | Asked By Phillip Roshak | Jan 14 15
4 Answers

Interior Basement Wall Advice

Hello all! Long time reader, first time poster.

I need some advice for insulating a full basement. Here's my situation and conditions as they currently exist. Hopefully I'm not forgetting anything.

-Location is right on the border of climate zones 4&5.
-Bare concrete block walls.
-The entire basement is below grade
-R-19 fiberglass insulation between the basement and first floor with kraft faced vapor barrier on the basement side.
-On some sections of the exterior wall, the sill plate is flush with the inside top of the wall.

In Energy efficiency and durability | Asked By Ryan Fitz | Jan 13 15
6 Answers

New cathedral ceiling with unfaced f/g batts, no air barrier or ceiling yet - planning t&g pine under...xps? below joists

Hello, all - first time post. I read all of the q&a posts I could find on cathedral ceiling insulation, and the article on how to insulate a cathedral ceiling, along with every response. So I'm informed, but still have questions about my particular situation.

In Energy efficiency and durability | Asked By Chris Johns | Jan 15 15
2 Answers

I am gutting the interior of my house and removing all the ceiling plaster and 1950s rock wool insulation. Is there a product I can use as a sheathing on the ceiling prior to putting up the drywall. We want to get the insulation in and the mechanicals bac

I am doing most of this work on my own, we are building new cabinets, ect. I am going to hire out the drywall hanging and finishing, but want to do that part all at once as oppossed to doing drywall now , and finishing later
Thanks Ralph

In General questions | Asked By Ralph Vickers | Jan 14 15
4 Answers

Airsealing an attic

Hello, I have a 172 year old brick home and have some questions regarding attic venting. My attic is in poor shape. It was "finished" when the house was built, with plaster walls, a flat plaster ceiling and 1 partition wall. I've been in the house about a year and am just now deciding to do some work up there. There are sections of sagging plaster and a few holes in the ceiling. I decided to widen a hole in the ceiling to peek up into the very top of the roof. The timbers look like they're in great shape but the masonry at the gable ends and chimney stacks are crumbling.

In General questions | Asked By Dan McGonigle | Dec 21 14
6 Answers

retrofit basement slab edge insulation?


Long time lurker, first time poster. Thanks for all the great info. Searched the archives, but cant seem to find an answer.

zip 12572, NY Hudson Valley Zone 5A

House built in 1961. on top of a hill, very good drainage, dry soil, no standing water after heavy rain, & 3ft eaves overhang walls

26' x 50' Monolithic Basement slab, guesstimate 4-6" thick. poured between the block/basement walls. [R20 basement walls internal insulation planned]

slab is on gravel /stone crush fill, assume no vapor barrier or underslab insulation.

In Energy efficiency and durability | Asked By p Ha | Jan 10 15
12 Answers

Creating more space for attic insulation

Ok, I'm sure this is a stupid question, but I really do appreciate all of the patient answers I have received in the past.

Because I will be building my home with blocks that are 1' tall, my top floor will be 8'8" from floor to the top of the tallest course of blocks, where the roof trusses normally rest. I really only need 8' ceilings on that floor. I got to wondering what to do with that extra 8", and came up with this idea to add some extra insulation since I would like to have a floor for at least part of the attic.

In Energy efficiency and durability | Asked By Stephen Youngquist | Jan 13 15
0 Answers

Triple Pane - Bristol Windows?

Anyone hear of Bristol Windows out of PA? They make a triple pane window but looking at the frame profile section compared to a European triple pane window, it's a night and day difference. The European frame is way beefier and reinforced with steel.

Just curious if anyone has seen these windows up close or used them?

In Green products and materials | Asked By Peter L | Jan 14 15
19 Answers

2 x 8 stud walls, or staggered?

Southwest Nebraska - Zone 5B - I experience all four seasons. Hot summers that can be humid some years. Cold winters.

Designing my home to build. Trying to determine which is the most cost effective method to do the walls. I am young, and intend on living in this house for a very long time.

In Green building techniques | Asked By Nicholas C | Jan 7 15
44 Answers

Disappointing phantom load on 27.2 SEER Fujitsu 9RLS2 minisplit

Looking for anyone with measurements of their mini-splits phantom and idle wattage use.

My newly installed 9RLS2 is using 80 watts, both when off and on but not running.
Other measurements while operating have been in spec range and are fairly impressive.

So I take it that SEER and HSPF ratings must not effectively measure/include phantom or idle loads. Heck just the fan at full speed uses only 25 watts

In Energy efficiency and durability | Asked By bob coleman | Jul 12 13
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