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nylicens
Sealing off attic ridge vents
nylicens

Ten years ago we bought an 1890's balloon framed house that was alum sided in the 50's. On move in we had to replace the roof within 90 days or the house insurance would be dropped. So in the midst of moving family and renovating the interior (iow, completely distracted) I told the roofer to NOT install ridge vents as there were no vented soffits on the eaves, so there was no reason to install them.  About 3 years ago, while having a gutter problem looked at, I finally realized that ridge vents *were* installed. Got an estimate of about 1K to have them torn off and capped. I am looking to see if it's possible to just use spray foam to accomplish the same task from the inside of the attic and not have the vents replaced. Any comments appreciated. 

Attached are pix of ridge board and closeup of ridge vent plastic mesh.

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FRANCO
Re: Sealing off attic ridge vents
FRANCO

 

What are ridge vents?

 

 

Critical to the attic’s health, ridge vents are part of the attic’s ventilation system. Installed at the peak of the attic, along the top ridge of the roof, the vents help to circulate air in the attic. They also usher moisture (in winter and summer) and hot air (during the summer) that would otherwise lead to damage.

 

Why do the vents leak?

 

With proper installation and care, ridge vents should not leak. However, improper installation leads to leaky vents. In some cases, installers will use the wrong nails or shorter nails to secure the vents to the structure. The loose connection allows the vents to shift in windy conditions, and eventually they will pull right off of the decking. The ridge vent sections should also overlap by about 1 ½ inches. When a shoddy or inexperienced contractor fails to overlap the pieces or doesn’t extend the sections enough, the vents will eventually leak. Another problem that can lead to leaking roof ridge vents involves sealant. A bead of sealant should continuously run along the sections of the vent. Without sealant, rain will access the space between the shingle and vent. The rain will eventually make its way into the attic.

 

Repairing leaking ridge vents

 

Avoiding problems with ridge vents is easy when you schedule an annual roof inspection. During the evaluation, the roofing contractor will not only assess the condition of the ridge vents, but he will also identify issues with shingle wear, damaged flashing and more.

Why contractors are switching to Mongoose!

 

• Unique design passes Dade County 110 mph wind driven rain test

• Mongoose Ridge Vent has 10.41 square inches net free area per

lineal foot – up to 19% more Net Free Ventilation Area than most other rolled ridge vents

• 8 mil polypropylene protective cover prevents leaks if ridge cap shingles are damaged or blown off and is clearly marked for alignment and nailing.

• Adheres directly to the roof for ease of installation without nails

• Protective cover is clearly marked for alignment and nailing

 

nylicens
Re: Sealing off attic ridge vents
nylicens

Well Franco, thank you for the info, but these ridge vents do nothing but let noise into the attic. My attic has no vented soffits so the ridge vents are not much use in circulating air.

Valerie
Re: Sealing off attic ridge vents
Valerie

An unfinished attic space should be ventilated to prevent the moisture from the living areas from migrating thru the ceiling and condensing on the underside of the roof. If the attic is part of the living area insulate under the roof with vapor barrier toward the inside. If you are doing a completely new roof you can install a product which has a nailing surface bonded to several inches of foam board.

Valerie
Re: Sealing off attic ridge vents
Valerie

An unfinished attic space should be ventilated to prevent the moisture from the living areas from migrating thru the ceiling and condensing on the underside of the roof. If the attic is part of the living area insulate under the roof with vapor barrier toward the inside. If you are doing a completely new roof you can install a product which has a nailing surface bonded to several inches of foam board.

nylicens
Re: Sealing off attic ridge vents
nylicens

I guess I should have mentioned that the ceiling of the living space is insulated. I want to insulate the attic with an eye to eventually installing a mini split heat pump to let us utilize the attic for storage of artwork. I am looking to keep the attic space to lower than 80F and higher than 45F. 

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