Gaps under skirting are one of those small snags that bother people far more than they should, given how minor the fix usually is. You notice a sliver of daylight under the board by the window, or a draught along the hallway floor in winter, and suddenly it is all you can see every time you walk past.
In a lot of Hampshire houses, especially the Victorian and Edwardian terraces and the timber framed cottages further out towards the New Forest, the floor itself is not flat, and skirting fitted in a straight line simply cannot follow every dip and rise without leaving a gap somewhere along its length. Understanding why the gap is there tells you whether a bead of caulk will sort it or whether the board needs to come off and be fitted properly.
Why gaps open up in the first place
Skirting boards are cut and fitted straight, but very few floors are. Old joists sag in the middle of a run, floorboards cup and shrink with the seasons, and screeded floors in extensions often settle slightly differently to the original structure they meet. All of that shows up as a wavy line where the floor meets the wall, even though the wall itself is straight and true.
Timber movement adds to it over time. Skirting, especially softwood, shrinks across its width as it dries out in a centrally heated house, and that shrinkage is rarely even along the whole length of a board, so a gap that was not there when it was first fitted can appear a year or two later, particularly in rooms with underfloor heating or a wood burner that dries the air out.
Poor fitting in the first place is the other common cause. Skirting fixed only to the studs or masonry without being scribed to the floor, or fitted quickly with a few nails and no real attention to the profile of the floor beneath it, will show gaps wherever the floor dips even slightly, which in an older house can be most of the way along a wall.
How to check what you are actually dealing with
Run a straightedge, or even a long spirit level, along the floor next to the skirting to see whether the floor itself is genuinely uneven or whether the board has simply been fitted proud of it in places. If the floor rises and falls by more than a few millimetres over a metre or so, that is a real slope, and no amount of filler will hide it convincingly for long.
Check whether the gap is consistent along the whole run or only in short sections. A gap that appears only near a door threshold or where two floor coverings meet is often just a levelling issue at that one junction, whereas a gap that gradually opens and closes along a long wall points to a genuine slope in the floor structure.
Have a look underneath if you can, through a floorboard gap or an access hatch, to see whether there is settlement in the joists themselves. That matters because if the floor is still moving, seasonally or otherwise, any fix you do this year may need revisiting, and it is worth knowing that before you spend money on a permanent looking repair.
- Straightedge along the floor to check for genuine slope versus poor fitting
- Note whether gaps are consistent along the wall or only in short patches
- Check under the floor where possible for joist settlement
- Look at the skirting itself for shrinkage cracks or warping
- Consider the room's heating, since dry air speeds up timber movement
Caulk: when it is fine and when it is a sticking plaster
For small, cosmetic gaps of a couple of millimetres, a good quality decorators caulk applied neatly with a wet finger and painted over is a perfectly sensible fix, and it is exactly what most decorators do as standard. It moves slightly with the timber, it is cheap, and it takes ten minutes a room.
Where caulk falls down is on genuine sloping floors with larger gaps, particularly anything over about five millimetres. Caulk will bridge a small gap but it will not hold its shape or its seal over a gap that size for long, and it tends to crack, discolour or pull away within a year or two, especially on a floor that still has some seasonal movement in it. At that point you are just repeating the job every winter rather than solving it.
Scribing and packing: the proper fix
Scribing means fitting the skirting board so its bottom edge is shaped to follow the exact profile of the floor beneath it, rather than assuming the floor is flat. It is done by holding the board in place, running a scribing block or a compass along the floor to transfer its profile onto the back of the board, then cutting to that line so the board sits tight to the floor all the way along.
Packing is the other half of the job on more uneven floors. Thin timber or ply packers are slipped behind the skirting at the fixing points to bring the board out to a consistent line where the wall itself is not flat, which keeps the top edge of the skirting straight even if the floor beneath is not.
Used together, scribing and packing solve the problem properly rather than hiding it, and they are the right approach whenever you are replacing skirting anyway, doing a refurbishment, or dealing with gaps that keep coming back through caulk alone. It takes longer than a tube of filler, but it is a job that is done once.
What it costs to have this sorted properly
If you are just caulking existing skirting yourself, it costs the price of a tube of decorators caulk and an afternoon. Having a joiner scribe and refit skirting in a single room typically runs from around 200 to 450 pounds depending on the length of run and how uneven the floor is, and a full house of skirting done properly with scribing throughout tends to sit somewhere between 1200 and 2800 pounds depending on size and the standard of finish.
It is worth weighing that against the fact that a proper scribed fit, done once, should not need revisiting, whereas caulking a genuinely sloping floor is a job you may find yourself doing again every year or two.
Give us a call
If gaps under your skirting keep coming back no matter how often you caulk them, it is worth having someone take a proper look at the floor before doing any more patching. Call us on 02380 201687 or 07833 227576, or email info@vipwalls.co.uk, and we can tell you honestly whether it is a scribing job or something simpler.
Common questions
- Why do gaps under skirting boards keep coming back after I caulk them?
- If the floor genuinely slopes, caulk is only ever a temporary bridge and it tends to crack or pull away as the timber moves seasonally. A permanent fix usually means scribing the skirting to the actual profile of the floor rather than filling the gap after the fact.
- Is a sloping floor in an old house something to worry about?
- A small slope in an older Hampshire property is very common and usually not structural, but it is worth checking underneath if you can, or asking a builder to look, if the slope is significant or seems to be getting worse. Most cases are simply the building settling over many decades.
- Can I scribe skirting myself?
- It is achievable for a confident DIYer with patience and the right tools, particularly on short, simple runs, but getting a tight scribe on a long wall with an uneven floor takes practice. Many people find it quicker and tidier to have a joiner do it, especially for a whole room.
- Does new flooring cause skirting gaps?
- Yes, quite often. Fitting a new, thicker floor covering or removing an old one changes the height relationship between the floor and the skirting, and it can either close up existing gaps or open new ones depending on the difference in thickness.
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