When buying carpets from us it is always advisable to allow an extra 5 inches on any width or length, then round up to the nearest Buying Room Plan. For example, if the length is 10 feet, you would probably need 10.5 feet of carpets so the fitter would have plenty to work with. As stated earlier, carpets generally come in 12-foot and 15-foot widths meaning one of the lengths of your room’s dimensions would need to under these. For most rooms that is fine, two walls over 12 feet is rare. If however your room does have two walls over like in our diagram you would need to round up the one measurement to 15 feet and buy 14’ x 15’ of carpet. Again, this is simple. If, however, both of these sizes were 15 feet instead of 12 feet, so 17’ x 17’ then even the widest carpet rolls would not be wide enough. You would need to have a join in rooms like this. Unfortunately, there is little else that can be done. You would need to work out how much carpet you need for the room. Taking our example measurements, 17′ x 17’, you would need to buy 18′ x 18’, then allow extra for the carpet you would need for the join. For a complicated room it is always worth drawing up a plan so as to aid in working out how much carpet you need (always allow extra so as you do not come out short).