Tiling a FloorDate: 06/30/99 at 18:23:02 From: Melissa Subject: Math conversion of yards and feet If you have a 12 ft. x 15 ft. square room, how many square yards is it? Is it 20? Also, for a 30 square foot room how many 8" x 8" tiles would you need? Thank you so much. Date: 07/01/99 at 08:38:36 From: Doctor Rick Subject: Re: Math conversion of yards and feet Hi, Melissa. You are correct about square yards. First convert the linear dimensions from feet to yards: 12 ft = 4 yd, 15 ft = 5 yd. Then when you multiply yards by yards, you get an area in square yards, namely, 4 yd * 5 yd = 20 square yards. Tiling is trickier because tiles around the edges will probably need to be cut, and this will require that you buy extra tiles. The first approximation, ignoring this complication, works like this: 1 square foot = 12 inches * 12 inches = 144 square inches 30 square feet = 30 * 144 square inches = 4320 square inches 1 tile = 8 inches * 8 inches = 64 square inches 4320 square inches / 64 square inches = 67.5 tiles Now for the complication. Let's suppose the room is 5 feet by 6 feet, or 60 inches by 72 inches. Divide each length by the width of a tile to find out how many tiles will fit across that direction: 60 inches / 8 inches = 7.5 tiles 72 inches / 8 inches = 9 tiles In an ideal situation, you could have 9 tiles by 7 tiles = 63 tiles, plus a row of 9 half-tiles (made from 4 1/2 whole tiles) along one side, totaling 67 1/2 tiles, the same as I got before. But having tiled some bathrooms, I know that the room is probably not quite rectangular. The standard way to tile a floor is to start from the center and arrange it so you have at least a half tile all around. Having cut tiles along all the walls allows you to compensate for irregularities, and everything looks symmetrical. In my hypothetical case, I would center a rectangle of 6 by 8 tiles, leaving 1.5 / 2 = 3/4 tile on either side in the short direction, and 1/2 tile on either side in the long direction. | | |<----- 9 tiles = 1/2 + 8 + 1/2---->| +-+---+---+---+---+---+---+---+---+-+ --- +-+---+---+---+---+---+---+---+---+-+ ^ | | | | | | | | | | | | +-+---+---+---+---+---+---+---+---+-+ | | | | | | | | | | | | | +-+---+---+---+---+---+---+---+---+-+ | | | | | | | | | | | | | +-+---+---+---+---+---+---+---+---+-+ 7.5 tiles = 3/4 + 6 + 3/4 | | | | | | | | | | | | +-+---+---+---+---+---+---+---+---+-+ | | | | | | | | | | | | | +-+---+---+---+---+---+---+---+---+-+ | | | | | | | | | | | | | +-+---+---+---+---+---+---+---+---+-+ v +-+---+---+---+---+---+---+---+---+-+ --- This adds up to 6 * 8 = 48 whole tiles 2 * 8 = 16 tiles cut to 3/4 2 * 6 = 12 tiles cut to 1/2 4 corner tiles cut to 3/4 by 1/2 -- 80 tiles total You might get away with fewer tiles than this (by using both halves of the half-tiles), but I would buy the full 80 tiles to be on the safe side. Home repair books give a formula to figure all this out; I don't have access to mine right now. I hope this helps a little. - Doctor Rick, The Math Forum http://mathforum.org/dr.math/ |
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