Wall AC box fastening

House Repair Talk

Help Support House Repair Talk:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

gottodo1

Well-Known Member
Joined
Apr 14, 2013
Messages
184
Reaction score
31
Hi All,
As always I wait to the last minute to finish anything. I built a wall ac box because I replaced my AC unit and the old box didn't fit. It used some metal wire to hold the box on. I'd like to use something like draw latches to hold it to the house now but for the life of me I can't find a draw latch with a strike that was designed to do this The box would be perpendicular to the wall and all the strikes designed for that are for tool boxes and I don't think would work. Any ideas on where I could get one?

I could make a strike but I've never worked with metal before so I would need some guidance on how to do that.

Any help would be appreciated. Wasn't sure where to post this.. it's pretty random. http://www.mcmaster.com/#standard-draw-latches/=uc8or0

I'd like to spend less than $10 to be fancy otherwise I grab some 50 cent eyebolts and use a bungee cord...
 
So this would be a wooden box built to fit around the outside of your AC unit, and it would have to fasten to the wall of your house? What kind of siding do you have?
 
Neal,
I should have noted I found those but they are $16 a piece so $32 to attach both sides to the wall. NEVER go zinc plating, even if chromate conversion coated. It's a wood fiberboard siding hardy board is what they call it here. Siding will probably be replaced in a few years with seamless steel. I can buy the stupid things at menards for $3 a piece but it doesn't have the right strike plate. These things aren't holding up 100 pounds I'd just like 1 or 2 PSI holding the box against the wall so the sealing foam compresses to provide a better seal.
 
How about a furring strip attached to the wall, and then hang the box on it. You could fasten straight down into the strip.

Or you could put the strip on the box (all four sides if you'd like) and then fasten straight into the siding. I'm not all that thrilled about putting holes in the siding, but a clamp or latch would have to do the same.
 
Last edited:
Here's a photo of the box (not sanded and finished). I put a piece of foam on the edge but it's not enough to compensate for the spacing between siding pieces. There's a bit of insulation in the back to help slow down airflow into the opening of the AC box.

I also don't mind drilling holes in Siding you just put a bit of silicone in before you put in the screw and it's all good.

That silver piece is the old mounting hardware but it didn't really hold it as the hole in the wood was stripped out from years of use...

IMG_20141029_110240133.jpg
 
Last edited:
I just made a box out of closed cell foam and put it together with gorilla tape. It covers on 5 sides like yours and is so light I don’t need to attach it to the house I just push it on and that’s it. It has held up for about five years now. I figured the 2 inch foam was much better insulation than wood and it keeps the wind out nicely.
 
But the hole in the wall should be trimmed and flashed with as much detail as a window to keep the water out when it rains. Then the top of the winter box should have a slope so water runs away from the house. Just a little water over time equalls rot in wall.
 
If nothing else, a coat of paint to match the house would certainly make this look more finished - and protect the wood somewhat. Neal is right (no news in that) the top could use a little pitch.
 
Neal,
Good suggestions and if I was in Indiana or somewhere with snow/sleet/rain all winter I definitely put some significant pitch but here in ND it either rains or it snows, and after Oct it only snows :(. I did cut in about 3 to 5 degrees of pitch on the box but nothing significant.
I had thought about trimming and flashing it when I replaced the old AC but I figured if the siding/wall stood up perfectly for 25 years without that, what's 1 or 2 more until I reside.

Slow,
Yes I said it was unfinished I just put it up for this forum post to show what I needed for fasteners, which I still haven't found reasonably priced. I will sand and paint or maybe Stain & poly it... haven't decided which yet.
 
Rain is one thing but your box is a cold zone so when the cold meet the warm moist air in the house you will have condenstion. Likely somewhere between drywall and siding.
I would leave it for the siding job too but you want to have a good look at windows and stuff like this when you do that. Maybe adding that foam to the box might be a good idea.
 
why not pull the ac in the winter, store it in the garage. make a slide in door /plug with siding insulation to go into the hole
have the outside trimmed with your soffit trim. to match the house.
 
The AC would slide out but there's a screwed in casing or shroud for the unit. I could pull the guts but I'd still have the case. ehhh it's a box I'll fasten it this year and figure out something for next.
 

Latest posts

Back
Top