mahogany porch flooring, which way up?
Hi All…I’m new here and have an interesting dilemma I’d like to share.
I just had a wraparound mahogany porch installed and the thing looks beautiful. I’m concerned about a few things, and can’t seem to find any info to settle my fears:
The porch flooring is tongue and groove and the flooring manufacturer has finished it on both sides, but one side has a slightly beveled edge. This is the side that was installed facing up. Will water and dirt collect there, and what does one do about it? This brings me to my next fear…the porch has no measureable slope.
The way I see it, the porch should have been installed smooth side up with a slope. Is this correct? If so, what options are there? It’s already installed with the bevels up, and the result is a porch that looks like a deck, except no gaps exist.
I can’t find any information to install the decking either way. I THINK the bevel surface is for vertical installation only, such as siding. For horizontal installation, I think it should be smooth, and a installed with slight slope away from the house.
Anybody have resources for such information?
Replies
Much prefinished flooring has a bevel, sometimes called a micro-bevel, so that any slight milling/installation differences from board to board aren't noticeable, since you won't be sanding it to level boards. Don't know if that's your case or not.
This is "Scenic" (a Plunkett Webster product) Mahogany 4/4. The bevel is about 1/8" radius, which leaves a groove 1/4" wide along the length of the boards.
Help clear things up any?
If your decking was pre-finished by the manufacturer, that bevel you mention is pretty typical for the reasons already mentioned. Dirt certainly will get in there as will water. I'd be more concerned with the water because of the long term problems it could cause. You're concern about the lack of slope is right on. If there are no gaps between the deck boards, you should have a minimum slope of 1/8" per foot away from the house. The boards should be installed so that their length is parallel to the line of slope. That way, any water that gets into the groove between deck boards can run along the groove and get out.
So now you have a porch that can't drain water because it has neither gaps between the decking nor slope. I'd get in touch with your Contractor. This seems like a pretty major oversight to me. I would imagine that after removing the decking, a slope could be retrofitted onto the structure either by shimming the inside edges or planing the exterior edges (but not too much or you'll affect the strength of the joists).
The flooring wasn't "prefinished", only correct in dimension. It requires sealing and staining before completion.
What worries me is this: If there's a groove, the slope should be in the direction of the groove. That's fine. But, when installing groove side up, the boards at the perimeter run perpendicular to the water flow "upstream". Where will this water go? As I see it, it has to permeate the joint, and destroy the materials. It has no clear path outwards. It's trapped.
"The flooring wasn't 'prefinished'"
"The porch flooring is tongue and groove and the flooring manufacturer has finished it on both sides"
These two seem at odds.
Do you have a digital camera? A picture would help some of the deck/porch experts here understand the issues with less guesswork.
Yes, I do. Since I'm new here, I'm unsure of picture limitations/file sizes.
I'll snap a couple photos tonight for upload or email
Sorry about the confusion of terms. I meant to say the flooring is milled on both sides, one side results in smooth seams like a bowling alley floor, the other results in gapless valleys about 1/4" wide V shaped 1/4" deep. The flooring manufacturer supplies the material unfinished with respect to sealers, stains, etc. and the contractor had to seal the woodwork on all 6 sides. This was done by staining/sealing the underside (the side that's got no bevel), installing the flooring, then staining/sealing the exposed side after install.
If you install with the bevel down, you have to sand the the whole floor to make it nice and flat. The bevel is there so you can't see the minor variations in thickness of the planks. Flooring is usually made to be installed that way. Sometimes, but not always, you can turn it over. If the floor is laid flat-side up, there is also a possibility of getting some splinters at the edges.
How are you measuring the slope? A cheap level is often pretty inaccurate. A good slope is around 1/8 inch per foot. Not really highly visible. Any halfway competent contractor would be unlikely to build it with no slope. Make sure you check the slope with a good level. If there really is none, that's a major oversight and a major issue to fix. Perfectly level is not good, insufficient slope away from the house may be tolerable, but any slope back towards the house is not acceptable at all.
I actually took the contractor's word for the lack of slope. Since the slope is seemingly more of an issue than the bevel, I plan to verify the slope this evening, and post the results.
Doc,
Is the porch covered? I'm assuming it is 'cause you call it a porch and not a deck.
Bevel up.... or bevel down and sand the floor.
Factory finish Mahog. will be fine under cover...slope or no slope.
Old wooden boats...Ditchburns for one......do just fine when exposed to a little water.
Ditch
It's covered, but not enclosed. It's already been wet after the roof has been installed.
It's large! 8x35 in front,wrapped to an 8x40 on the side. Stairs along the entire length, also mahogany. The roof covers, but has nothing to shield from driving rains, it'sabout the the equivalent of an exposed deck, especially when considering the lack of sunlight the floor receives.
Doc,
Standing water?
Ditch
Is it really mahogany? Swietenia macrophylla? What a terrible use of a tropical forest species!