# Proper way to install half round dormer vent?



## Git (Mar 11, 2008)

I live in S Cal and recently added a couple of whole house fans to cool the house off at night. I also wanted to add some more of these "half round dormer vents" that are already on the house.









The roof is your standard for Cal, concrete tile, and the house is 6 years old. I took a close look at how the builder installed the vents, and this is what I have so far:

I found the same vents at Lowes and made a template to cut out for the opening. I then cut out the concrete tiles and had to remove one of the tiles to the left of the opening because the nail was in the way of me sliding in the vent. These roof tiles have two nail holes per tile, and it looks like the installers only used one nail per tile, so once I cut the nail, I could slide the tile down and out"











I then cut out the hole for the opening - approx the same size as the builder installed vent:










I then was able to slide the vent in for a test fit:










Here is my question - what do I use to secure the vent and the one loose roof tile in place?

I see Lowes carries a couple of different caulking tube type products that looks like it would be pretty easy to work with
1) Black Jack weather proof cement $3.22 per tube
2) Black Jack rubber flash cement $6.12 per tube

When I look at the builder installed vents, there are no visible nails but I can see where they have used some type of cement to glue down the flashing towards the bottom. My thoughts are to liberally smear the bottom of the flashing with one of the above products and then slide the vent into place. I could also try to get a couple of nails down through the flashing at the bottom and through the original nail holes in the roof tile?

I still need to pull the vent out to paint it and then complete the final install

Anyone see any problems?


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## Leftyho (Apr 12, 2009)

Hi,

That piece of copper wire you have laying there. Nail it to the deck. Slide the tile in place with the wire sticking out the bottom. Leave about 3/4" of the wire there. Cut the rest off. Then bend the wire up. Use 2 wires one at each end of the tile.


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## Red Squirrel (Jun 29, 2009)

Cement shingles? interesting. One thing you will want to do is ensure it is very well sealed as well or you could end up with water going through. Normally I believe it's tar that you use, but for shingles like yours, maybe cement will work? (I'm not an expert at this, just throwing ideas around)


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## tinner666 (Mar 14, 2005)

Like Lefty said. Use the wire to secure tile and as for the vent, I'd double over a couple of pieces of flat metal, (same as the vent), nail on each side of the opening and let it extend below the vent flange 3/4". 3-4 pieces are OK too. Side the vent in, fold the tabs over to secure the flange and you're done. No caulk necessary.


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## Ed the Roofer (Jan 27, 2007)

To secure the tile roofing in place.....

It depends on how sturdy and what guage the wire is.

I would rather use a 1" to 2" wide piece of flat copper stock nailed in with copper nails and long enough to extend lower than the butt edge and then fold up and on top of the bottom edge of the tile, usinf 2 of these hooks to hold each piece of tile in place.

Ed


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## Scuba_Dave (Jan 16, 2009)

If you can access the vent from the attic - seems you can- what about drilling small holes in part of vent & using wire to secure the vent in place

Or is that what y'all are saying ?


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## Ed the Roofer (Jan 27, 2007)

I added an edit to clarify what I was speaking of in the previous post.

I was only providing a better type of hook installation for the loose tile roofing pieces.

Ed


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## Leftyho (Apr 12, 2009)

Hi Scuba Dave,

Your way would make a leak.

There should be no holes in the vent.

Ed, You will see your straps. The wire is practically invisible to the eye. It does not change the texture or color of the face of the tile. I use 12 gauge wire.


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## Git (Mar 11, 2008)

Well thanks for the help. I need to get the vents painted today (6 of them) and I will probably finish it up tomorow


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## Ed the Roofer (Jan 27, 2007)

Leftyho said:


> Hi Scuba Dave,
> 
> Your way would make a leak.
> 
> ...


I was figuring that the tile had a greenish hue and the copper would turn to the patina color.

Ed


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## Scuba_Dave (Jan 16, 2009)

Leftyho said:


> Hi Scuba Dave,
> 
> Your way would make a leak.
> 
> ...


There wouldn't be any hole in the vent itself, just the inner metal
In most of these vents metal extends in past where any rain would hit

I was thinking the older one was copper & weathered
But it does look like some paint flaked off?


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## Gary in WA (Mar 11, 2009)

Well, Ed, I see you are right on, again. At least to be historically accurate. 

"A broken tile should be carefully removed with a slate ripper or hacksaw blade inserted under the tile to cut the nail or nails holding it in place. If successive layers of tile are already in place covering the nailholes, it will not be possible to attach the replacement tile with nails through the holes, so an alternative method of attachment will be necessary. By nailing a tab of double thickness copper stripping on the sheathing below the tile, the new replacement tile can be slipped into position and secured in place by bending the copper strip up with a double thickness of the copper over the tile. A slate hook or "tingle" can be used in the same way. This fastening system functions in place of nails (Fig. 16)." 

Taken from: http://www.historichomeworks.com/hhw/pbriefs/pb30.htm#How Tiles are Attached 

Be safe, G


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## Git (Mar 11, 2008)

I did some more searching around a found some info from another concrete tile manufacturer - MonierLifeTile

This is more what I was thinking originally, although I could certainly understand the use of another mechanical means to hold the tile in place, especially when dealing with slate and steeper pitched roofs


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