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0 Answers

Main stack venting

I'm finishing tying in an addition to my existing slab on grade home and found the main stack vent on the existing house is about 6" into what will be a hallway.

The original house had a 3" main stack vent off the master bath, near where the drain exits the house to the septic. There is also a 2" vent on the other side of the house connected to the kitchen and another full bath. There is a 3rd full bath in the middle of these two vents. The original master bathroom piping has been capped and covered with concrete, except the main stack vent.

In Building Code Questions | Asked By Mike M | Jul 22 17
0 Answers

Accessing a concealed duct unit

My HVAC contractor will be installing a Fujitsu 9RLFCD and a 12RLFCD. Each of the slim duct units will share space in closets and hang vertically. I don't have a utility room for them to be exposed in.
Now I need an idea on how to conceal the slim ducts but still make them accessible.
Do they need ready access like a breaker panel or can all the seasonal coats be hung in front of them? Are there pre-made access panels for sale?
What is a "good practice" for finishing these off? Any pictures?

In General questions | Asked By Mark Walker | Jul 22 17
2 Answers

Naive question on LEED certification


In General questions | Asked By Brian Gray | Jul 21 17
3 Answers

Energy efficient dryer vent

I was looking for a suggestion on a through-wall dryer vent for 8" thick wall that's energy efficient?

In Energy efficiency and durability | Asked By Michael Brackett | Jul 22 17
7 Answers

1870s rowhouse rehab energy efficiency - radiators and radiant heat?

I'm looking for feedback on heating and cooling (and energy efficiency) for a large, three story brick, italianate 1870's row house (with low-sloping flat roof) - it's attached to the neighboring brick house on the south, with a few feet between houses with the neighbor to the north). This is a big (4000 sq. ft), brick, main street structure with massive walls and many average sized (15' x 15') rooms that can't be opened-up too much because of the existing structure.

In Energy efficiency and durability | Asked By humbleadobe | Jul 21 17
0 Answers

One more PEX (safety) question!


I've been reading over information regarding the safety of PEX for the last few days. It's safe to say, there is a lot of uncertainty and varied opinions on which type of PEX to use.

I have read over some of the posts here on GBA but am still not sure which to go with.

Several users have mentioned a weird taste in their water when using PEX A and that PEX B is the safest in regards to chemical leaching. One reviewer stated: "A-type PEX leaches 50-200% more chemicals into the water".

In Green products and materials | Asked By Tommy87 | Jul 22 17
0 Answers

Want to install mini-split need advice

Hi everyone!

Our master suite has only 1 small ac vent, none in the closet or bathroom, this makes it very uncomfortable in the summer in Florida. We have a large slider window and a really small double hung window in the bathroom. This makes windows units not a good choice as I've tried to install many without success.

We have a flat roof over this part of the house so we can't run more ac to the other rooms.

3 walls are outside walls, one wall is concrete the others are basic construction, minimal insulation and no insulation on the roof. Both windows are double pane.

In Mechanicals | Asked By jgraeff | Jul 22 17
7 Answers

What is minisplit short cycling? Turndown?

I understand that a "somewhat" oversized mini split will generally run at a more efficient rate, as opposed to an undersized mini split, which will run full-out, and therefore be less efficient. It sounds as if the problems with oversized mini splits would be 1) wasted money on oversize equipment, and 2) decreased dehumidification, due to the equipment not running enough. Am I about right, so far?

In Mechanicals | Asked By Ben Rush | Jun 25 17
3 Answers

portable dehumidifiers

Are there any that are as efficient as Santa Fe? And durable/reliable too? I need something that extracts about 40 pints a day.

In Mechanicals | Asked By charles CAMPBELL | Jul 21 17
2 Answers

Humidity and negative pressure

A customers home (zone 4 non-marine) has condensation problems (summertime) on a particular HVAC duct. Upon inspection the %RH was at 60%. There is a whole house dehumidifier hooked in with the HVAC System (Fan runs at low speed continuously) Bathroom exhaust fans are backflowing and letting in a significant amount of heat, and when opening the front door one can feel the hot air entering the house. There is no ductwork in the attic, it is all in the basement.

In Mechanicals | Asked By Jeff Classen | Jul 20 17
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