Vent a Hip Roof

albasaurus

Greetings,

I have a split level home in Madison, WI home. I am about to embark on insulation and venting work. 2/3 of the home has adequate ridge to place a ridge vent.

1) What kind of ridge vent is best for my area? There are many large maple trees everywhere with helicopter seed pods..... Omni low profile, vs Cobra (which kind is best), vs Shingle Mate II?

The other 1/3 of my house (2 story portion, 700 sq feet) has a hip roof with only 2-3 ft of ridge to vent with. Presently I have three old school box vents on three of the four sides about 1.5 - 2 ft from top.

2) What is the best venting method for the hip portion of my split level that would not work in conflict with the ridge vent on 1 story portion of my home? Should I stick with the box vents, move the box vents up, ridge vent the hip ridges, cupola, etc?

Thanks!

Alex

Gary in WA

Maybe a roofer will follow up......

http://www.airvent.com/professional/...hipridge.shtml

http://files.buildsite.com/dbderived...rived20936.pdf

Be safe, Gary

__________________

seeyou

Sounds like the box vents are fine, function wise. If you want a different appearance, the cupola idea is good. Another option would be dormer vents.

Attached Images

  

Gary in WA

A picture would be nice...........

Be safe, Gary

__________________

albasaurus

Thanks Seeyou and GBR for the replies:

Well, I am not computer savvy enough to post a picture. However, I think I may be able to give a better idea through words.

My hip roof has four ridges (diamond) that come together at the top ridge which is only about 1.5 - 2' long. The roof is approxiamtely 3.5/12" decline. Due the main ridge from which the hip ridges are posting from being so short, I don't think that a hip ridge system is valuable. Mid-America hip ridge system requires begining hip ridge cut out 36" from main ridge if the ridge vent will not continue onto a traditional ridge. Since the main ridge is only 1 - 2 feet in length, its not possible to have a ridge vent on it: cut outs requiring 12" from ending of ridge.

So that leaves me with box vents or dormer vents. I am beginning to lean towards domer vents. I was going to place a dormer vent on three of the four sides of my hip roof (none on the front). Couple questions:

1) How far from the top/ridge should the dormer vent be placed?

2) Is it worthwhile to put two dormer vents on each side, and if so, how much space needs to be left between dormer vents should I decided to put two on each side?

3) Any recommendations on dormer vents? I would like to find one that is black.

4) Are there any other parts that I will need if installing dormer vents?

Any other suggestions, advice, contrary information, please send!

Thanks ahead of time,

Alex

Alto

I am right in the midst of a roofing job on a hip roof and had lots of the same questions. I had insufficient space for a ridge vent and also felt that I might get leaks with a ridge vent. So I used some old fashioned passive vents. The Owens Corning web site helped me figure out how many I needed. It turned out to be four that provided 144nfa each, though I ultimately bought mine from Air Vent. They have turned out to be quite a bit bigger than I expected and at first I was pretty shocked. But I have decided that it is not too different really than the old ones and really you can't see them too much. Put them on the back of the house and in my case I have a pretty large flat roof in front of them that creates an favorable angle for not seeing them. They are raised up a lot more than the old ones, which hugged the roof a lot more. so I think you can get lots of air running through. As with the ridge vent you need sufficient soffit nfa for these things to work right. The OC site will give you the calculation also for relative soffit to passive vent. I am satified that this was the right thing to do with a hip roof with as small an area as mine.

seeyou

1) How far from the top/ridge should the dormer vent be placed?

Typically, a dormer vent is placed about a 1/3 to 1/2 way up the roof. If you're using them for inlet, lower would be better. Cut a cardboard cutout of the face of the units you're interested in and set it on the roof to get an idea how they'll look. If using more than one vent, they'll likely perform similar to gable vents, with one being inlet and one or more being outlet. If you install them low, a ridge vent might be advantageous.

2) Is it worthwhile to put two dormer vents on each side, and if so, how much space needs to be left between dormer vents should I decided to put two on each side?

If you need that much venting, it won't hurt. Cosmetics would be the main focus on placement.

4) Are there any other parts that I will need if installing dormer vents?

Maybe some replacement shingles and some underlayment. Depends on the model.

3) Any recommendations on dormer vents? I would like to find one that is black.

I only make them from materials that are solderable (copper, zinc), due to leaking concerns. I've made some from galvanized to be painted, but I feel it's a poor material for that application. I'm not familiar with anyone that makes them with kynar coated steel, but you may be able to find some. Good luck.

albasaurus

Thanks Copper,

I am planning on using the dormer vent as an outlet for air rather than an inlet. I have adqequate ventilated soffits for my air inlet.

Should a dormer vent be placed as outlet/exhaust?

If so, how does that affect placement? My initial impression is to place the dormer vent as close to the ridge as possible.

I am looking at dormer vents as a possible solution to venting my hip roof.

Thanks,

Alex