Hey Guys,
First time posting here, Ive been an online member for some time now. I have a project coming up and just wanted to get any feedback as to how to approach this particular job. My client wants to take an existing back deck (the overall dimensions are 8′ x 16′) and enclose it into an entry way/mud room. The house is a two-family, located just outside of Boston. The deck gives access to the rear entrances of both the upstairs and downstairs appartments. In order to access the basement, where the laundry areas are located, those living in the upstairs appartment have to “brave the cold” while doing laundry and it is for this reason she wants it closed in. I already plan on tearing out the existing framing of the deck, it appears there were some rot issues that were somewhat addressed, but not entirely. There is a roof structure above, and after further inspection, it does look to be in good shape, so I would like to brace it temporarily while building the new platform underneath. I have also planned on installing some rigid foam insulation in the floor and was considering these other techniques:
-As far as the subfloor goes, because it would be exposed on the underside, would it be a good idea to account for a layer of pressure treated plywood (1/2″ or 3/4″) and then the 3/4″ TG Subfloor over that ?
– One of my main concerns is how to approach finishing the inside of the mudroom. My client seems set on tile for the floor, which seems to be the best choice. But as far as the walls are concerned, would there be any issues with installing sheetrock because it will not be heated or cooled? The longest wall of this room will be mostly windows, and there will be exterior doors on either end leading to stairs, so in the summer they could be opened to allow for ventilation, my main concern is mold resulting from humidity, and possibly having cracking in the joints due to the temperature changes. Perhaps using something such as densarmor or one of thos “paper free” brands would be a good idea?
These are some preliminary ideas I had, so any feedback, tips or experience with this type of situation would be greatly appreciated guys, Thanks!
Replies
You say the decking has to go, you are going to enclose it, sheetrock it, paint it, and put in many windows and tile it. Sounds pretty nice, too nice for some hacky cold subfloored deck system.
The deck is going to be gone, why not pour a footer and crawlspace wall and do it right? If tile floors are in order you need a solid floor anyway. Just seems like you are 90 of the way to a nice sun room/mudroom, and with all the windows you mention a screened room for summer. Just not sure it would cost that much more.
If still interested in the deck arrangement, as I understand it two layers of subfloor is good, but you need adequate joists and beams to limit any movement to avoid cracks. And even then, given an unheated space above and below you may have expansion and contraction issues. (not an expert by any means).
Thanks for the insight DoRight. As always cost is an issue. The actualy deck itself is about 4 feet off the ground, and the overall span off the house is only 6 feet, so I considered using 2x8, maybe even 2x10. Do you think there would still be deflection issues with the tile if there were 2x8 or 2x10s with the two layers of plywood over top? I was thinking of using an uncoupling membrane for the tile such as ditramat to help as well, what do you think?