The holiday season marks the arrival of plenty of celebrations, good food and an excuse for inviting family and friends over, but it also marks the arrival of the cold weather. For many northern states this means high bills come New Year, something many people can ill afford at the moment. According to Lawrence Berkeley National Laboratory, a typical US family is now spending over $2,000 a year on utility bills, of which, heating is by far the biggest portion. In particular, those that live in older homes face the steepest costs in keeping warm, and in a time of financial pressure, getting those costs down has never been so important.

The problems with older homes, is that all too often heat has many ways of escaping. Draft excluders can temporarily seal doors and windows that were fitted decades before and no longer sit in their frames so snugly, but one area, which is not so easily cured, and where drafts can cause room temperatures to plummet, is the flooring. Drafts blowing up through the floorboards can make sitting in some rooms of an older house really uncomfortable. In most older homes, this is due to the flooring having changed shape due to years of being walked on, and the continuous expansion and retraction of the wood caused by temperature changes. But sealing it can be a real challenge.

Strip flooring is particularly difficult to seal as the expansion and shrinkage caused by temperature changes means regular filler will just pop out of the gaps. For flooring on upper levels, things are not as difficult as the gap between the ceiling and floor can be filled with regular insulation, but for downstairs rooms this isn’t going to work. One way is to cut pieces of insulation to fit into the bay between the floor joists and flooring, and then caulk the seam where the insulation meets the floor joists, which will help the insulation cope with the growing and shrinking of the wood. This, however, is a timely operation, but there is a simpler solution.

You can fill the gaps between the floorboards themselves with something that can cope with continuous expansion and shrinking of the wood and not pop out – rope. Yes, regular rope is ideal for sealing floorboards. The rope needs to be just slightly larger than the gaps that need filling, and it’s best to wait until the room is at its coolest and when the gaps between the floorboards are at their widest. By soaking the rope, and then rolling it tight and jamming it into the gaps, using a screwdriver, you can seal all the gaps.

Because the rope has been applied wet, it will slightly expand when it dries but will have enough give and elasticity to cope with the shrinkage and expansion of the wood. Once you’ve allowed the rope to dry, simply stain it to match the color of the flooring. It’s perhaps best to stain the entire floor to ensure continuity in color, but this is far quicker than having to remove the floorboards to get at the joists. Properly done, the rope should seal the flooring for years, preventing drafts and coping with the expansion and retraction of the flooring caused by winter and summer temperatures.

Izzy Woods is a freelance writer and ardent DIY-er. She’s a green fiend, so she tries to use organic mattresses and local building materials, but appreciates the environmental benefit of doing it yourself.