[scottyja]

We have a 2,300 sq. ft. single story, southwest-style home that was built in 2004. We get some heavy monsoons in the summer, but is usually pretty dry the rest of the year. During a recent heavy monsoon we had some roof tiles come off and a leak that did some ceiling damage. That has been repaired, and when the roofer left he mentioned I should get an attic fan up there. The temps here in Tucson, AZ can get over 110 F and I'm assuming much, much hotter in the attic.

I've been doing some research on attic ventilation and now I'm concerned the attic isn't properly ventilated, and I'm not sure a fan will help. Basically, our attic has two very large gable vents (I'm estimating 48" x 24-36").

East:

West:

But as far as I can tell, there don't seem to be any soffit vents or anything else on the lower line of the attic:

I thought building codes required attics to have soffit vents? Am I missing something or is my new home not built to code?

Second, will putting an attic fan on one of the gable vents do that much to help lower some of my cooling costs? Any advise will be greatly appreciated!

 

[TazinCR]

Anything you can do to move that hot air will help. An automatic attic fan only runs when needed.

 

[DIYtestdummy]

Tucson! Northwest side?

Your roof isn't poorly designed - those newer houses are just built horribly. I hate to be blunt to a neighbor, but it will just be one thing after another. They are supposed to be more efficient, but my utility bills are less in my brick home than my buddy's and he just had to replace one of his new leather couches because his roof caved in with the start of the Monsoons. This is a 2006 house in Rita Ranch. Lucky for him, he's moving.

 

[scottyja]

I'm pretty close to Rita Ranch myself. For the most part, any shoddy craftsmanship has been easily repairable, but there's no way to get up there and add soffits the way it currently exists. I guess I'll throw a fan up there... better than nothing!

 

[Grumpy]

A fan on the interior of the gable vent will create a wind tunnel and may help very much. www.airvent.com www.rollvent.com two great sources for attic ventilation information.

You don't NEED soffit vents, and yes you don't have them. Soffit vents with a ridge vent is a preffered method of ventilation because it works veritcally which is heat's natural movement... Hot air rises. However a horizontal movement of air is also acceptable so long as there is movement. That's my problem with gable vents, they don't often work unless there is a strong wind. Thus introduce the interior gable fan.

 

[scottyja]

Thanks all for the help. I went ahead and ordered the Air Vent APG. It's rated just about right for our home size. I've heard it's important to install them to blow with the wind rather than against it. I'm really not sure which way the wind will be blowing during the summer. I think I'll just install on the East facing vent since it's much easier to get to.

 

[Ed the Roofer]

Did they use any Hip Stringers at all?

Look at that stack of Hip Caps on the bottom of the hip.

Are the voids filled in with mortar, or even an alternative product, or just left wide open to the elements?

By the way, a tile roof is one of the coolest roofs as far as interior heat build up, due to the air gap under the product, yet above the roof deck sheathing.

Ed

 

[scottyja]

Did they use any Hip Stringers at all?

Look at that stack of Hip Caps on the bottom of the hip.

Are the voids filled in with mortar, or even an alternative product, or just left wide open to the elements?

By the way, a tile roof is one of the coolest roofs as far as interior heat build up, due to the air gap under the product, yet above the roof deck sheathing.

Ed

Now you're going to find out how little I know about roofing. I'm not quite sure what Hip Stringers are. All I know is there is a fair amount of tar paper under the tiles, and that's what was replaced by the roofers. How everything connects at the ends... I'm not too sure.

Is there something specific I can look at? If so, I could take a picture and post. Thanks for the reply. Speaking of cool roofs, I called the roofers back and asked them about an attic fan, and they said they didn't think it would be necessary, given the existing insulation and type of roof. I assume they meant the tiles. Still... it gets pretty toasty up there.

 

[Ed the Roofer]

A Hip Stringer on a tile roof, which probably can go by other names, but that is what I was taught, is the 2" x 4"s or multiple 2" x 2"s stacked on top of each other on the Hips, so that the Hip Tiles can be fastened properly to a solid substrate, without having to use a pole barn nail or a 6" to 8" long screw.

By looking at the bottom of the hip, you can see the multiple stacks of Hip tiles to get that bottom piece up to level with the field tiles.

By looking upwards along the entire Hip, it looks like a big giant gap between each course of Field tiles and the Hip tiles.

A compound, which usually is mortat is embedded into those gaps to seal the openings between them, to make those areas weather-tight.

Ed