Wednesday, March 12, 2014

Adding Soffit Vents Is It That Easy



Home built in 86', stucco on wood frame, about 900sqft of main attic above the second floor and all I have is two gable vents. I used a smoke pen and there is pretty much no air movement what so ever up there. In summer the upstairs cooks and you can feel it through the ceilings. Winter it is the opposite. I spoke with my neighbor yesterday who has an identical home and she said they had the same issue with their home. Three years ago they has soffit vents added and an attic fan which she swears drastically changed the cooling and heating of their home.
Are soffit vents that easy to install? On my garage I see the bird hole type soffits with mesh screen behind them drilled out but that does not correspond to the upstairs of my home and do anything. I saw soffit covers at HD in which it looks like I would just have to cut out a hole in the wood soffit and stick the vent in and be done. Is that the case? I would like to add some soffits and even a gable vent fan to get air circulating better after air calculations of course. I also plan on adding 12 more of insulation but want to get the venting proper first.

Do you indeed have soffits, meaning the roof hangs out past the exterior wall and has a horizontal underside exposed to the outside air such as would be the case on ranch style house?
If so, I would recommend installing insulation baffles between the rafters/trusses at the top of the exterior wall and then install perferated soffit material to admit air to the attic. And also install ridge vents on the roof ridge to allow the attic air to escape.

Correct, the roof hangs over the exterior, in line with the exterior wall are 2x4's between each rafter which I assume are the soffits correct? I did plan on installing the baffles which just slide into place for the most part correct? What do you mean install perferated soffit material, I assume this is the soffits material i saw at HD? Also a ridge vent is out of the questions, I don't have the funds for that and I have an all tile roof.
Thanks

ff....I have the same thing as you, only a rancher of about 1600sf. I priced 2 snap in vent caps from a wholesale builders supply, thought I would just drill 2-3 holes per bay and snap them in. Need at least that many to get any benefit, the 2 only provide something like 3/4 free area, which is what you are concerned with.
Don't have the info anymore, but I would have spent something like $300 just for the vents. I have 2 turbine vents in addition to 2 large gable vents...but it still gets real hot, going to do something probably this year.
Since you have tile..the small caps will be your only option, but since its a 2 story, its gonna be a royal pain (and kinda dangerous) to install them. You might be able to drill the holes (gonna need a lot of bits and a good corded drill!) and take a piece of PVC pipe to move the insulation out of the way, then install baffles later if needed. My roof has a very low slope (yours too?) and getting out to the edge from the attic is a real bear.

GunGuy: I'm a little confused, why would the 2 snap in be my only option due to the tile roof? There is enough clearance for me to get my drill or sabersaw in the area i would need to put the new vents. I saw ones that were like 4x10 I believe for like $1.97 a piece. I can easily get to the soffits on the back of the house but front of the house would be tricky, that also brings me to another question, would I have to add soffit vents to each side of the house or can I get away with just the rear if I can get enough ventilation that way? Luckily my attic has a pretty good amount of room, I have prob 10ft dead center and it pitches down from there to the sides. I should be able to get out towards the edge without to much issue from the attic.
Is this the type of soffit vents you are referring to, only yours are a little smaller?
Master Flow 4 in. x 4 in. Plastic Wall Mini Louver Vent White (4-Pack) - RLSC4 at The Home Depot

Perhaps I misunderstood your description. This is what my soffits look like...
[IMG][/IMG]
In the front and back (where the gable vents are) the stucco goes all the way up to the roof sheathing...so no way to do anything there.
I don't know the exact terminology and can't find a good image...but normal soffits come straight out horizontal from the wall and meet the end of the rafters, and there is no blocking between the rafters/trusses. So air can flow up from under the roof through the soffit and out the gable or roof vents.
Maybe yours are different..but this is very common construction up here. Something like this back in VA would be strange indeed.

I can't see the picture at work but from your description I think I know what you are referring to. For my house the soffit vents are in line with the exterior wall. If you were to follow the wall up to the top you would have an open eve that hangs over and where the rafters meet the exterior wall in between each one is a 2x4 (I think its called a bird Soffit?)
I have provided links to two pics, if you look at the first one that is how my rafters are set up with the blocking in between, the second would almost be how the soffit vents would need to mount. Hopefully they links work but if not google image Bird Soffit
http://t1.gstatic.com/images?q=tbn:A...X7MNXS9THo1A_-
http://t0.gstatic.com/images?q=tbn:A...Cv9NB-al5joIsk

Yes...same kind of stuff. I just can't get my head around how you would use a jig saw (or any saw..) to cut rectangular holes in a 2x4 from either side. Try cutting a rectangular hole in a 2x4 with a jig saw even when its easily accessible...not easy! If you were planning to just drill...even then, try putting a wood bit in most drills and be able to drill a hole w/o hitting the roof.
What I meant about only option with a tile roof..was some sort of soffit vent. Ridge vents CAN work with gable vents, but you can't install them...so the only way to increase the flow is from below.

I can get access to it fairly easily but i do have to verify how thick the wood is up there. If its not that thick it shouldn't be to bad. Maybe its not ax actual 2x4 between the rafters, I just assumed it was. I will dig into a little more today and see exactly what I am up against.

Saw your image gunguy and yes that is how mine look. I guess I will see what is the easiest approach is once I get up there and start measuring but I'm pretty sure I can lay out a template, drill some pilot holes and work the jig saw that way without to much trouble.

Bumping this up, is it going to be an issue only putting soffit vents on the back of the house? I have no way to even get to the front part of the house. Its beautiful out tonight I went up in my attic just to see how it was and it is at least 20degrees hotter right now. Nothing is circulating up there.

For best results, you should vent both front and back of the house. If yours is like GG45's, I would remove the blocking between the rafters at the top of the wall, install insulation baffles, install vents in the blocking, and re-install the blocking.

How would I go about removing and re-installing the blocking? I know for best results I should do the vents on both the front and back but right now I really have no way of getting to the front. The front of the house has two tiers of tile roof tops. If I were to throw a ladder up to get to the top of the roof the angle would be unsafe (to horizontal). I guess i could possibly try from the inside of the attic but even then it would leave limited room to work with.
Would it still work just doing the rear of the house?

With all due respect to wirepuller.....I can't even imagine taking out and reinstalling the blocking. We're talking major surgery with a sawsall and a really ugly look after trying to put them back. Pretty sure mine are nailed though the rafters into the blocking and the sheathing is also nailed into it. And cutting openings through a bunch of 2x4s with a jigsaw.....brrrrrr...makes me cringe. I'd rather drill a bunch of 1 holes, shove some schedule 20(?) thinwall pvc though past any insulation and figure out a way to cap the outside that doesn't look like crud.
FF...we really need some pictures...http://forum.doityourself.com/electr...your-post.html

can get you pics thats not a problem but it looks just like the picture you posted. Is there anything in particular you want pics of?

Maybe just some longer shots, so the Pros understand the issue. I'm kinda fuzzy on when you talk about front and back...but that could just be orientation of the house. Almost all of them in my area have the peak front to rear.
Any extra air flow from the bottom will be a benefit.

Use a hole saw to cut the 2 holes into the blocking WITHOUT removing it. Sorry wirepuller, but I'm with GG on that one. The blocks are butt nailed at one end, toed on the other, and probably have the sheathing nailed down from the top as well.
The bird blocks will slide right in. Depending on the exact diameter of the ones you use, you may need to tap them in with a rubber mallet, or you may need to put a little dab of silicon into the hole (bottom 1/3 or so) and slide the bird block into it. Just installed about 200 of them at my parents house last year. Had to go to 2 different stores to get that many, and the diameter was slightly different. Some needed the mallet to get them in, others slide right in.

Lefty, your saying to use the existing bird blocks and drill out 2 holes and below you are saying replace the bird blocks..... Am I not reading that right?
Gunguy, I will snap some shots tomorrow and post them up. Only reason I can get to the rear soffit areas of the house is because I have a covered porch which gives me access to get up those easily. The front of the house is a lot harder for me to get to.

Thanks, guys for being easy on me. I will admit my suggestion would be a LOT of work. I am mainly concerned about insulation behind the blocking. Until that issue is resolved, the vents will not help much.
Now I see what the problem is with doing the front of the house. I guess I would not want to set a ladder on a tile roof either.

fox_forma, you didn't understand what I said. I'm saying leave the wood blocks in place, drill the holes in them, and install the birdblocks -- the 2 metal vents -- in those holes.
Wirepuller38, of course we were easy on ya!!
I totally agree with you about the insulation having to be pulled out of the way for the vents to work. But that is probably easier to accomplish from inside the attic using a rake as opposed to cutting out the blocking. Easiest rake that i've found to us in an attic is one that the width of the head can be adjusted on. Look in the garden center at a local box store or other garden center.

Ah I see what you mean Lefty, when you said install bird blocks I was pituring the actual soffit bird block. When I was at lowe's yesterday grabbing some stuff they had 6x16 bird blocks already drilled out and I thought that is what you meant. I checked HD's website and they had larger soffit vents, on their site they say aluminum but they also had vinyl ones which I thought would be best. 2 holes I can do as well but I would need a lot more placed to cover how much air intake I need.
Construction Metals Inc. 16 in. x 4 in. Aluminum Soffit Vent in Brown - FOV164BR at The Home Depot

Man...I just can't imagine drilling that many holes and having to pry the plugs out each time. I think when I figured mine out at 3 per bay it was about 180. Lefty....how many hole saws did you go through?

Actually, I used my Milwaulkie right angle drill with a 2 auger bit to drill the holes I had to drill. And about 2/3's were already done -- I wasn't starting with totally solid boards all the way around like you are.






Tags: adding, soffit, vents, easy, bird blocks, drill holes, exterior wall, soffit vents, tile roof, between rafters, front back, front house, gable vents, back house