Fixing a hot attic

[firecadet613]

I bought a new to me home last year and the attic is very hot, so much so that it's causing the upstairs to be much warmer than the downstairs (even moreso than our last house, which had a lot more sun exposure).

The roof is new and I've adjusted the HVAC vents and have the thermostat using an upstairs sensor, so it's not too bad, but damn. Go into the room with the attic access and it's hot!

I did a quick search online and it appears that the most common resolutions are:

- sealing the attic
- adding insulation
- adding ventilation (powered attic fan)

I think I'm good on the first two, no other room is really warm.

Has anyone added an attic fan? What were your results-oriented? Is this something a roofer would install? If not, then who?

 

[WhitleyStu]

If you have gable ends it is an easy install for an attic fan on a thermostat. We set ours at 80°F and it made quite a difference in cooling the house. If you don't have the tools it is a quick job for a carpenter

 

[Brandon]

How deep is your insulatuon? How is the attic access insulated?

For an immediate "fix" turn your furnace blower to "on".

It will take a day or so to blend the air but it will help -some.

 

[Leo]

I also like a Thermostatic attic fan. Mine vents just the attic.

I have also had one that pushes house air into the attic, from the hallway. The idea is that it pulls air into the house through open windows. That is nice a few times a year, but most of a hot, humid summer you cannot use it.

 

[PGRChaplain]

Make sure the artic is properly Vented. Soffit Vents and a Ridge Vent are the most efficient. An Automatic Vent Fan helps evacuate the Hot Air.

 

[blain]

Are the ceilings upstairs flat or do they follow the roof line up?
Plenty of soffit venting is great. I have a gable roof and had vented soffit installed the whole length of the roof, when I last replaced the shingles.
I like the idea of powered attic vents, but not so much for them being installed in the gable ends. That simple tends to pull air from the end of the house and not the whole length of the roof line. Air, like water takes the path of least resistance.
A powered attic fan (or two), mounted centrally, high in the roof allows for more air to be pulled in across the soffit edge and under the decking, cooling more of the actual roof. Poor soffit venting can lead to shingles getting baked, brittle and curling.
A good alternative to mains power is solar powered. But low cheap, quality fans don't hold up over the long haul.

 

[1nderbeard]

I also like a Thermostatic attic fan. Mine vents just the attic.

I have also had one that pushes house air into the attic, from the hallway. The idea is that it pulls air into the house through open windows. That is nice a few times a year, but most of a hot, humid summer you cannot use it.

We lived in a 1923 craftsman house with a giant attic fan like you describe. You're totally right. It was nice like 2 days a year. The rest of the time it was useless.

 

[Ruger_Ronin]

I bought a new to me home last year and the attic is very hot, so much so that it's causing the upstairs to be much warmer than the downstairs (even moreso than our last house, which had a lot more sun exposure).

The roof is new and I've adjusted the HVAC vents and have the thermostat using an upstairs sensor, so it's not too bad, but damn. Go into the room with the attic access and it's hot!

I did a quick search online and it appears that the most common resolutions are:

- sealing the attic
- adding insulation
- adding ventilation (powered attic fan)

I think I'm good on the first two, no other room is really warm.

Has anyone added an attic fan? What were your results-oriented? Is this something a roofer would install? If not, then who?

As mentioned, an electric exhaust vent fan wired to thermostat. Kicks on around 105° - 110°. Cheap and easy.

 

[GodFearinGunTotin]

We had a Cape Cod style house that had this problem. We added more insulation, fixed the venting from the soffits up to the ridge vent, and added an electric attic fan. We went from having to add an extra room AC in the rooms to not needing it/them at all.

It's getting to a bad time of the year to start that project now. I certainly don't envy you.

 

[firecadet613]

Thanks for the replies all!

When the sellers put on a new roof, they stuck with the standard vents (with soffits) on the back side of the roof, I wish I could have had them change over to the ridge vents, but we honestly didn't think they were doing the roof until it happened, a handful of days before closing.

Pretty sure the attic access is covered with just a piece of drywall with no insulation on the back, I'll swing by Menards and try to grab a small piece to lay over it (our old house had a 4" piece of insulation over the drywall cover).

Both ends of the roof have gable ends, but having a fan centrally located higher in the roof (behind a vent) makes sense.

Not the best time of year to be screwing with this, and it's definitely within my capabilities to install a fan, but I may hire this one out

 

[blain]

Check out the QuietCool AFR_SLR_40 at Menards.

 

[Leo]

These actually work very well, but most wives (and HOA's) don't like them

Master Flow 12 in. Weathered Wood Galvanized Steel Internally Braced Dual-Bearing Wind Roof Turbine GIC12WW - The Home Depot

The GAF Master Flow internally braced turbines are efficient, easy-to-install venting options for your roof. They allow heat and moisture-laden air to escape your attic, helping to extend the life of your roof. They are designed with upper and lower steel ball bearing systems for years of...

www.homedepot.com

 

[firecadet613]

Check out the QuietCool AFR_SLR_40 at Menards.

These actually work very well, but most wives (and HOA's) don't like them

Master Flow 12 in. Weathered Wood Galvanized Steel Internally Braced Dual-Bearing Wind Roof Turbine GIC12WW - The Home Depot

The GAF Master Flow internally braced turbines are efficient, easy-to-install venting options for your roof. They allow heat and moisture-laden air to escape your attic, helping to extend the life of your roof. They are designed with upper and lower steel ball bearing systems for years of...

www.homedepot.com

Thanks! I was looking at styles like these. Would they just replace the vent on the rear of my roof? Any harm in doing one of each over those vents?

This is what I have currently on the back of the roof (just a stock pic I found online).

 

[Ark]

My dad retrofitted our old house with full lenth soffit and ridge vents. Marked and cut the entire run with a circular saw. Blown insulation in the attic to the thickness of the ceiling joists. Hot air exhausts out the ridge vents and chimney effect draws cooler air in through the soffits. Worked freaking great, never saw mold or condensation or other issues in the attic.

 

[Creedmoor]

Make sure the artic is properly Vented. Soffit Vents and a Ridge Vent are the most efficient.

This right here, Vent it correctly and let natural convection cool the attic.

 

[firecadet613]

My dad retrofitted our old house with full lenth soffit and ridge vents. Marked and cut the entire run with a circular saw. Blown insulation in the attic to the thickness of the ceiling joists. Hot air exhausts out the ridge vents and chimney effect draws cooler air in through the soffits. Worked freaking great, never saw mold or condensation or other issues in the attic.

This right here, Vent it correctly and let natural convection cool the attic.

I do have full length soffit vents on this home, same as my last home. Same roof vents on both homes. Attic insulation is higher than the ceiling joists (same on both homes).

The only difference is my last home was in a subdivision and had full sunlight on both sides of the roof, all day. The new home is in the woods and the north side of the roof gets zero sun, the back side of the roof partial sun (when it's not blocked by trees).

We had some light mold issues in the attic of the new place, but only the north side of the roof where it doesn't get sunlight (this home is 25 years old). In our old home, the attic was spotless...but it gets full sun to heat it up and burn anything off.

Not sure how the lack of sunlight plays into it, but I need to get this figured out ASAP.

Glad I came to INGO vs just getting someone to throw a fan in!

 

[Creedmoor]

I do have full length soffit vents on this home, same as my last home. Same roof vents on both homes. Attic insulation is higher than the ceiling joists (same on both homes).

The only difference is my last home was in a subdivision and had full sunlight on both sides of the roof, all day. The new home is in the woods and the north side of the roof gets zero sun, the back side of the roof partial sun (when it's not blocked by trees).

Can't figure out what's causing the heat issue, but would like to resolve it ASAP.

Heres a question, my brothers home had the same. full soffit vents and ridge venting.
but zero air was flowing through the attic space.
What we found, was underneath the vented soffit was unvented plywood.
We pulled the vinyl and hole-sawed 4" holes and popped in theses screens the local roofing store had and then reinstalled the vented soffit.

 

[blain]

Your mold situation is probably due to poor air movement in the attic, rather than a shaded roof.
Get that air flowing, to exhaust the moisture and keep the decking as cool as possible.

 

[firecadet613]

Heres a question, my brothers home had the same. full soffit vents and ridge venting.
but zero air was flowing through the attic space.
What we found, was underneath the vented soffit was unvented plywood.
We pulled the vinyl and hole-sawed 4" holes and popped in theses screens the local roofing store had and then reinstalled the vented soffit.

Good question! I will have to check it out. I would hope not, but can't hurt to check.

 

[Gingerbeardman]

Ridge vent is fairly easy iirc. Mark a line about 2 inches each side of the ridge with a chalk box, set your circular saw to just over the depth of shingles and plywood, cut it out, nail down ridge vent. I don't know if it's the best option for you as I was always the "do it" part of the operation, not the "think it" LOL and it's been years since I did construction.