Solar Roof vents

[GottaB 596]

Turns out hail means I’m getting a new roof. Totally forgot about ROFL BOX, my bad, or I’d have reached out. We are going with Crest Roof and USAA has already sent us the cash.

 

The brochure from rest mentioned solar vent fans. I asked and the guy from crest suggest one solar vent fan and two box vents to bring the temp down. The roof guy said we could buy them and they’d install them.

 

Our AC is in the attic and has trouble keeping the house cool enough during the summer.

 

Are these worth it? Which ones should I lean toward or stay away from?

[Updawg 2334]

Why not ridge vents instead?

[ROFL BOX 6650]

1.  Fuck you.

 

2.  Need to see an overhead view of your house.  Go to Google Maps, find house, zoom in & show only the roof (+ maybe a bit of the yard, whatevs).  Paste pic into MS Paint, edit out as needed... then copy the entire image, paste here (if using a computer... otherwise, screenshot on phone, crop / edit & post via TapaTalk).

2a.  I can't make a suggestion without seeing the roofline... the GAF versions are good & Attic Breeze is well regarded (in the proper sense, not Shag lexicon).  If you have a mostly hipped roof (pyramid type shape), then yes, a power fan (solar or hard-wired) is a good way to go.  The benefits of solar is you won't need to worry about a drunk electrician who wired something wrong & it fails or catches the house on fire.  The benefits of hard wired is they have more power & will slurp more air out of the attic.

[ROFL BOX 6650]

1 minute ago, Updawg said:

Why not ridge vents instead?

Because possibly hip roof, that's why.

[GottaB 596]

My bad.

The only ridge vent is that small section at the top.

[TeeDubya 3362]

following.  soaking up smarts.

[ROFL BOX 6650]

Based on that layout, I would only do a power fan in these two spots (blue squares) & if ridge vent, in these pink lines.

Keep in mind (& it is possible that your saleshole doesn't actually know this):

1.  ONE 4' piece of ridge vent has the same air flow as 4 'static' vents (holes in the attic, whether a turbine or any other covering device).  This is according to GAF, the largest shingle manufacturer in the USA.

2.  If you buy a turbine, it will cost around $ 40.00 for a quality unit.

2a.  One single stick of ridge vent retails for around $ 10.00.

2b.  This would mean that a single piece of ridge vent costs 25% of the price for a turbine, but a turbine gives you 25% of the air flow on a single piece of ridge vent.

 

Also... intake opportunities are important.  I am assuming your house was built within the past 20 years & if so, that means your soffit is most likely a Fiber Cement product & has air flow all over the place... lots of holes to allow air in.  & That's good.  "Balanced" air flow for a good "Ned Free Air Flow" (NFA) is what you're after.  Gable vents don't suck (nor blow) all that well so if you have a gable roof, stick with ridge vents.

Finally... you probably won't see a lower AC bill for the new attic fans or a ridge vent.  Proper insulation, quality sealing around windows & AC ducting & doors... all of that affects your interior comfort & leaks that send cool air into the attic / hot air pushing down into the house.  YES, a cooler attic is important.  Your equipment in the attic won't suffer quite so bad from insane summer head (easily 140 degrees on a quality hot day) & shingle manufacturers specifically say that you need to have good air flow to prevent cracking & other long term damage to the shingles.  Bad air flow can void your warranty.

[Onboard 2.0 9083]

55 minutes ago, ROFL BOX said:

1.  Fuck you.

 

 

This was THE proper Surly response.

[ROFL BOX 6650]

Forgot to include the pic.



...AND... you do not mix exhaust products, meaning no ridge vent AND any other hole in the roof within a minimum of 10 ft. apart.

So my pic is either / or, not both.

[RPM 26433]

1. Screw Surly member out of work. Give money to Rando.

2. Get Surly member to give you their professional knowledge to tell Rando.

3. ???

4. Profit?

[deadshank 24653]

2 hours ago, ROFL BOX said:

1.  Fuck you.

 

Awesome.

[GottaB 596]

Thanks again for responding. Should Texas hail destroy my roof, I’ll PM you first.

The house is 6 years old and yes the soffits have holes in them.

I’m assuming powered vents are better than non powered


That back section is the covered patio, if that matters.

[deadshank 24653]

2 hours ago, GottaB said:

 

Turns out hail means I’m getting a new roof. Totally forgot about ROFL BOX, my bad, or I’d have reached out. We are going with Crest Roof and USAA has already sent us the cash.

 

The brochure from rest mentioned solar vent fans. I asked and the guy from crest suggest one solar vent fan and two box vents to bring the temp down. The roof guy said we could buy them and they’d install them.

 

Our AC is in the attic and has trouble keeping the house cool enough during the summer.

 

Are these worth it? Which ones should I lean toward or stay away from?

 

Your AC compressor is in the attic?  Really?

FOR THE 1  BILLIONTH TIME:  Roof vents' (ridge vents, wind turbines, box vents, turtle vents, power vents, solar-powered vents) primary function is to vent out HUMID air from your attic in both the summer and winter.  Humid air renders fiberglass, rock wool and cellulose insulation ineffective.  The secondary function is to relieve a little bit of heat. 

Your AC compressor is probably not in the attic and it is most likely on the ground outside of your house in......the hot sun where it can function properly despite the heat.  

If your AC has trouble keeping your house cool you may have an insulation problem where the cool air under the ceilings is being overrun by the hot air in your attic.  Your attic (if traditionally vented) is supposed to be hot in the summer and cold in the winter.

Powered roof vents typically suck.  Some of the solar-powered roof vents are pretty good.  Attic Breeze, in our experience, make the best solar-powered roof vents.

CHECK YOUR INSULATION.

[GottaB 596]

Your AC compressor is in the attic?  Really?
FOR THE 1  BILLIONTH TIME:  Roof vents' (ridge vents, wind turbines, box vents, turtle vents, power vents, solar-powered vents) primary function is to vent out HUMID air from your attic in both the summer and winter.  Humid air renders fiberglass, rock wool and cellulose insulation ineffective.  The secondary function is to relieve a little bit of heat. 
Your AC compressor is probably not in the attic and it is most likely on the ground outside of your house in......the hot sun where it can function properly despite the heat.  
If your AC has trouble keeping your house cool you may have an insulation problem where the cool air under the ceilings is being overrun by the hot air in your attic.  Your attic (if traditionally vented) is supposed to be hot in the summer and cold in the winter.
Powered roof vents typically suck.  Some of the solar-powered roof vents are pretty good.  Attic Breeze, in our experience, make the best solar-powered roof vents.
CHECK YOUR INSULATION.

Ok. That makes sense. Point received and this is why I asked. You’re right, my ac compressor is outside. The fan is inside. Thank you. The benefit (cooler attic, which might aid my ac) is overstated for what my interest in a solar fan would be. I figured while I was getting the roof done, I’d look into the options. The ridge vent I already have may be sufficient for it’s purpose.

[GottaB 596]

As far as the insulation, you gotta guy?

[Onboard 2.0 9083]

1 hour ago, GottaB said:

Thanks again for responding. Should Texas hail destroy my roof, I’ll PM you first.

The house is 6 years old and yes the soffits have holes in them.

I’m assuming powered vents are better than non powered


That back section is the covered patio, if that matters.

Power anything is always better, power steering, power plays, power ties....

[NeverMarryAStripper 22054]

Power on the electric grid

[deadshank 24653]

17 minutes ago, GottaB said:

Ok. That makes sense. Point received and this is why I asked. You’re right, my ac compressor is outside. The fan is inside. Thank you. The benefit (cooler attic, which might aid my ac) is overstated for what my interest in a solar fan would be. I figured while I was getting the roof done, I’d look into the options. The ridge vent I already have may be sufficient for it’s purpose.

Best Insulation

512 560 8714

 

We use these guys in Houston for insulating our houses requiring spray foam.  I believe they will do blown-in fiberglass, as well.  Axck them.

[ROFL BOX 6650]

12 hours ago, deadshank said:

Your AC compressor is in the attic?  Really?

1.  He never said the COMPRESSOR is in the attic & I assumed that (like prob. 90% of modern houses) that his air handler is the part that is occupying the attic (that's why I mentioned the equipment suffering... the air handler will get an easier life if the attic temps are reduced).

2. re: insulation, I am slowly becoming a "not fan of" spray foam because we have in the past 5 years or so encountered probably 7 or 8 spray foam houses where the exact source of the leak cannot be determined due to the foam.  Leak shows up down here, point of origin is... um... well... somewhere up above?  Dunno.  Water got between the deck & foam, then ran down slope quite a ways before it finally popped out somewhere.  Even worse if under a metal roof.

 

Back to your roof layout:  hot air is still being trapped here, even though it's the porch.  It has a fully intact "underside", so the air isn't moving out, only up (pic 1, L side).  This one measly little exhaust vent wont qualify for your shingle manufacturer's warranty against delamination.

 

Add ridge vent here (pic 2, R side).

 

[Bernard 879]

My water heater is in my attic so I always figured a hot attic was saving me $$$ on my water heating bill. 🙂

Bernard

[deadshank 24653]

1 hour ago, Bernard said:

My water heater is in my attic so I always figured a hot attic was saving me $$$ on my water heating bill. 🙂

Bernard

What happens in the winter time, smart guy?  Huh?

[Onboard 2.0 9083]

3 minutes ago, deadshank said:

What happens in the winter time, smart guy?  Huh?

You move it.........D'UUUUUUUH !!!!

[GottaB 596]

1.  He never said the COMPRESSOR is in the attic & I assumed that (like prob. 90% of modern houses) that his air handler is the part that is occupying the attic (that's why I mentioned the equipment suffering... the air handler will get an easier life if the attic temps are reduced).

2. re: insulation, I am slowly becoming a "not fan of" spray foam because we have in the past 5 years or so encountered probably 7 or 8 spray foam houses where the exact source of the leak cannot be determined due to the foam.  Leak shows up down here, point of origin is... um... well... somewhere up above?  Dunno.  Water got between the deck & foam, then ran down slope quite a ways before it finally popped out somewhere.  Even worse if under a metal roof.
 
Back to your roof layout:  hot air is still being trapped here, even though it's the porch.  It has a fully intact "underside", so the air isn't moving out, only up (pic 1, L side).  This one measly little exhaust vent wont qualify for your shingle manufacturer's warranty against delamination.
 
Add ridge vent here (pic 2, R side).

 

Thanks again.

[elfenix 34396]

3 hours ago, Bernard said:

My water heater is in my attic so I always figured a hot attic was saving me $$$ on my water heating bill. 🙂

Bernard

until it's so hot your pilot light can't create enough chimney effect to draw in fresh air at the bottom and puts itself out constantly. 

[UT_OB1 2229]

@ROFL BOX or anyone else that might be able to help me with an insulation question 

 

We have a home in Galveston with vinyl over shiplap built in the 40s. I believe it has a decent amount of insulation in the attic, but it has no insulation in the exterior walls. It has a ~1” foam board begins the vinyl siding.

 

The ac seems to work mor than I feel like it should. We have 1/4-1/3 of the siding we need to replace, and I was wondering if it would be worth the trouble to pull down all the siding cut a 2” circular hole through the foam between each stud and blow in loose insulation. I’m concerned that the shiplap wouldn’t prevent moisture from getting in. Would I need to cover the foam in a moisture barrier after that?  Am I better off removing the foam?

 

It obviously would add quite a bit of work turning a large patch in to a complete siding redo. Is it even worth my time, or would I be better off blowing 8-12” more in to the attic?

 

for reference we used 2700 kWh last month  in a 21-2200 sqft home. 

Edited August 20, 2021 by UT_OB1

[ROFL BOX 6650]

Can you post up a pic of the siding?

1. I am assuming very few trees on the Western side (coastal area, etc)

2. What color? Dark = heat. More & more, for a "beach-y" vibe I am a fan of pure, snowblindiinglywhite & soft blues or a minty light green as a contrasting color.

3. In the pics, I would like to see what your soffits situation is like.

4. The shiplap wood is great as a nail able surface & I see no reason to take that off unless there is some other reason i don't know about.

5. Sight unseen, I might suggest removing the vinyl, staple on some batts or rolls of R-whatever stapled to the shiplap, then some R-max pegged on over the batts (getcha some long plastic caps & if you're adventurous, even a "Stinger" plastic cap gun... I have no idea what the maximum length is that it will shoot).

Vapor barrier ("house wrap") over that & then your vinyl. Hand nail the replaced vinyl siding to secure ¡¡HOWEVER!!! you need to make sure it isn't too thick a package from the vinyl to the shiplap.

Long roofing nails are available, however you do need to measure the depth needed AND don't make the nails penetrate too deep because the siding needs to expand / contact with heat, cold, etc.

Again, we need to see some pics.



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[UT_OB1 2229]

1 hour ago, ROFL BOX said:

Can you post up a pic of the siding?

1. I am assuming very few trees on the Western side (coastal area, etc)

2. What color? Dark = heat. More & more, for a "beach-y" vibe I am a fan of pure, snowblindiinglywhite & soft blues or a minty light green as a contrasting color.

3. In the pics, I would like to see what your soffits situation is like.

4. The shiplap wood is great as a nail able surface & I see no reason to take that off unless there is some other reason i don't know about.

5. Sight unseen, I might suggest removing the vinyl, staple on some batts or rolls of R-whatever stapled to the shiplap, then some R-max pegged on over the batts (getcha some long plastic caps & if you're adventurous, even a "Stinger" plastic cap gun... I have no idea what the maximum length is that it will shoot).

Vapor barrier ("house wrap") over that & then your vinyl. Hand nail the replaced vinyl siding to secure ¡¡HOWEVER!!! you need to make sure it isn't too thick a package from the vinyl to the shiplap.

Long roofing nails are available, however you do need to measure the depth needed AND don't make the nails penetrate too deep because the siding needs to expand / contact with heat, cold, etc.

Again, we need to see some pics.



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Let’s see what I can find…

 

Here we go.  Third picture shows how all the soffits are “designed.”  There’s about 25’ of that total around the house.  
 

The previous owner replaced about 2/3 of the siding at some point and it is still functional, just not the prettiest in the world. The back part of the house that wasnt replaced you can see in the worst of in the 4th picture.  It had gotten very brittle and cracked, and recently during one of the storms it took a section with it (lightning also struck the transformer on the street and blew it and one on pole 50’ away up)  

There was vinyl siding there. Under that black paper (is that for moisture?seems like wrong material) is a foam board, and under it is the shiplap. 

[ROFL BOX 6650]

1. In a storm, if you file a claim due to a covered peril (damage) & this pattern is not available any longer (measurements, not appearance), insurance policies should get you a minimum of an entirely new wall.

2. Lighter colors are good for less heat, won't absorb the sunlight or hold heat.

3. The "black paper" is old school, but a functional vapor barrier. Probably 30 pound.

4. If it was me, I would follow the plan laid out prior & use that for the best possible mitigation. Maybe even swap out vinyl for Fiber Cement. Is vinyl required due to "we want this to wash out in a hurricane" type codes? Maybe for some kind of new construction but not for a grandfathered structure where the shiplap was already in place & you are going back over that.

Galveston, eh? /Homer




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[UT_OB1 2229]

The part that was knocked and damaged by the storm is probably $200 worth of vinyl, not really worth going through insurance. I should probably keep it to just a patch job, but I kid of want to do a bit more of the house that is older if I’m going to do that. And like you said, cement board would be better, so in my head I’ve moved to why not just replace it all?  And if I’m doing that, I’m thinking I should try to add insulation for the exterior walls. 
 

I wasn’t planning on pulling off the shiplap. You mentioned stalling up some batts or rolls to the ship lap. How exactly does that work if I’m stapling to the exterior of the shiplap and don’t have the studs to crest a gap?  I’m just picturing flattening the insulation out when I put the cement board (or vinyl) siding on top of it. 

[deadshank 24653]

12 hours ago, UT_OB1 said:

@ROFL BOX or anyone else that might be able to help me with an insulation question 

 

We have a home in Galveston with vinyl over shiplap built in the 40s. I believe it has a decent amount of insulation in the attic, but it has no insulation in the exterior walls. It has a ~1” foam board begins the vinyl siding.

 

The ac seems to work mor than I feel like it should. We have 1/4-1/3 of the siding we need to replace, and I was wondering if it would be worth the trouble to pull down all the siding cut a 2” circular hole through the foam between each stud and blow in loose insulation. I’m concerned that the shiplap wouldn’t prevent moisture from getting in. Would I need to cover the foam in a moisture barrier after that?  Am I better off removing the foam?

 

It obviously would add quite a bit of work turning a large patch in to a complete siding redo. Is it even worth my time, or would I be better off blowing 8-12” more in to the attic?

 

for reference we used 2700 kWh last month  in a 21-2200 sqft home. 

Assuming you are insured through the Texas Cat Pool and you want to replace1/4 to 1/3 or your siding, you will have to follow their rules and may be cornered into replacing all of the siding per insurance regulations.  Further, you will need to look on the TDI web-site and get the list of pre-approved siding materials and the manufacturer of the material.  Once you establish which siding you will use, the siding will need to be installed and then inspected by a licensed inspection engineer (list of names is on the TDI  web-site).  If you want to use a siding product that is not on the pre-approved list, then you have to pay an engineer to give you the install instructions for the product you want to use, follow the instructions and have the engineer of record inspect and approve the installation and the product.

Read the rules and regs prior to starting a project like this.

[UT_OB1 2229]

Crap. I didn’t realize siding was one of the things tdi had to have an engineer sign off on.  Thanks for the heads up. That may turn this back in to a patch only job. 

[ROFL BOX 6650]

If the siding is no longer available (again, not for pattern or appearance but for dimensions & measurements), this IS a valid claim & it is possible your insurance company is on the hook for every single expense related to code compliance, engineers certs, etc.

Have you talked to a competent local contractor who has siding experience?

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[Onboard 2.0 9083]

2 hours ago, deadshank said:

Assuming you are insured through the Texas Cat Pool and you want to replace1/4 to 1/3 or your siding, you will have to follow their rules and may be cornered into replacing all of the siding per insurance regulations.  Further, you will need to look on the TDI web-site and get the list of pre-approved siding materials and the manufacturer of the material.  Once you establish which siding you will use, the siding will need to be installed and then inspected by a licensed inspection engineer (list of names is on the TDI  web-site).  If you want to use a siding product that is not on the pre-approved list, then you have to pay an engineer to give you the install instructions for the product you want to use, follow the instructions and have the engineer of record inspect and approve the installation and the product.

Read the rules and regs prior to starting a project like this.

Wow, is the engineer certified thing because of the high temps y'all get causing expansion, and contraction issues ? 

[deadshank 24653]

11 minutes ago, Onboard 2.0 said:

Wow, is the engineer certified thing because of the high temps y'all get causing expansion, and contraction issues ? 

Hurricane winds

[Onboard 2.0 9083]

28 minutes ago, deadshank said:

Hurricane winds

Ah coastal wind issues, got it.  Not sure that's required here even on the coast.  I've never run into that.  

We have to provide upgraded windows, and more robust braced wall design in all high wind areas.

[ROFL BOX 6650]

Ah coastal wind issues, got it.  Not sure that's required here even on the coast.  I've never run into that.  
We have to provide upgraded windows, and more robust braced wall design in all high wind areas.

Anything within 50 miles of the coastline needs an engineer's stamp / cert.

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[Bill Clay 48]

How much impact does shingle color have on attic temps? My newish neighborhood has a bunch of dark gray roofs. If vented properly, no big deal? You don't see too many lighter color roofs even in places like Arizona so I'm guessing the delta must be fairly small.

[ROFL BOX 6650]

6 hours ago, Bill Clay said:

How much impact does shingle color have on attic temps?

What color is your roof?  I assume also in the "Weathered Wood" family.  There's a reason summertime service in your attic (for the AC, water heater, etc) costs a lot - time spent in the attic is probably a max 10 to 15 minutes before someone has to get out of there.  I'm not joking about +130's F.

Attic exhaust as discussed herein is definitely going to assist, but it's also a sweaty affair.  Don't spend big bucks going to the sauna @ your gym, just pull down the garage ladder & spend 15 minutes up there.  If I could find & beat the guy who came up with "free inspection"...  Fuel, time, risk of death in the attic, etc.