Roof Vents only in 14x14?

[mahu]

Do roof vents only come in the standard 14x14 inches size or has anyone found 8x8 or 10x10 fans for roof mounting?

[wollip]

Search for - Heng's® Mini Roof Vent .

 

But it is just a passive vent. If you also want a built-in fan, I think 14x14 is the industry standard.

[KMG]

Try www.rvcenter.com.  Part number:17511-C1G

Might be the same unit Wollip suggested.  Good luck.

 

[mahu]

Thanks Wollip and KMG for the quick replies and your suggestions. The Heng's mini vent would be the size I had in mind.
I also found a 6 inch circular fan from Ventline which I am considering. I'd install one in the front over the kitchen for venting old air out and one in the back to bring new air in. Reversing the connection when installing will allow for reversing blade rotation. Capacity is rated at 100cfm and it'll keep dry while in operation in anything except really bad sideways rain according to reviews on youtube. 

https://www.etrailer.com/Enclosed-Trailer-Parts/Ventline/VP-543SP.html

[KMG]

Mahu, I like the round vent.  Easy to install.  Going to get one for my dog's igloo style doghouse.  Thanks

[mahu]

You are welcome! Decided to get two of them. One in the front over the kitchen for venting out and one in the back to bring fresh air in. Should provide nice air circulation. 

In terms of cutting out the round hole I found the perfect-sized hole saw here: http://www.automationdirect.com/adc/Shopping/Catalog/Tools_-a-_Test_Equipment/Hole_Cutting_Tools/Multi-Purpose_Hole_Saws_(HSS_-a-_Co_8)_-a-_Accessories/Cobalt_(Co_8)/126160

[KMG]

So how many times are you going to measure before you make the first cut?

[mahu]

Hehe...I'll let you know when I do. Can't do much structural work right now with the way it's been snowing in Squaw Valley. I am doing prep work and ordering all the supplies and appliances right now and will start conversion when Spring comes around, probably in early/mid March.

 

I am hoping since it's a circular cut and using a hole saw with a pilot drill I can't screw it up too badly. I'll probably get some sheet metal scrap pieces to make some practice some cuts.

[wollip]

If using a hole saw of this diameter is new to you, realize that it may try to slightly drift even with the center pilot bit helping out. It shouldn't be excessive - just enough to make you think it could have gone better. Using a slower speed might also work against you since it will tend to cut and stall - then jump or jerk slightly when you restart the bore.

I would drill from the top down (mainly to avoid the shower of metal particles that are going to rain down). But drilling top down also allows for wedging a length of 2x4 directly beneath the area (floor to ceiling). Let the pilot bit drill into this brace. If the wood is dense enough, it will pull the pilot bit down as the bore starts and help to stabilize the cut once the large diameter bit makes contact.

You have the right idea - practice first. A salvage yard might have a junker they'd let you use - if they like the box of donuts you show up with when asking.

[KMG]

Wollip's advice is great.  I also suggest using the hole saw to cut a hole in a scrap piece of 3/4" plywood.  Use the plywood hole as your template to aid in keeping the hole saw in place while cutting the roof. Also, I'd drill the pilot hole from the inside to insure correct placement then drill with the hole saw from the rooftop.  Good luck.  Don't forget to take a few pics.