Most sanding advice covers the same well-trodden ground: equipment, room prep, grit changes. This part focuses on two details that genuinely matter but rarely get proper attention, plus a quick rundown of the rest for anyone who needs the full picture.
Remove The Base Shoe First
Base shoe, also called quarter-round moulding, is the small decorative trim installed at the bottom of baseboards. It's genuinely worth removing before sanding starts, for two separate reasons. First, it protects the moulding itself from getting knocked or damaged by heavy sanding equipment working close to the walls. Second, and less obvious, sanding with an edger slightly lowers the floor level right at the perimeter, and if the base shoe stays in place, it ends up sitting on a small, awkward plateau once sanding is finished, rather than meeting the new floor level cleanly. Label each piece as you remove it, since matching it back to its original position afterward is considerably easier with labels than by memory.
Not All Stains Sand Out: Pet Urine Is Different
This is worth knowing before you assume sanding will fix every mark on a floor. Water stains generally disappear completely after a couple of sanding passes, since they typically don't penetrate deeply enough to survive the process. Pet urine stains behave differently. Urine reacts chemically with the wood's natural tannins, and that reaction can penetrate deep enough into the timber that it survives standard sanding depths entirely. These stains tend to look distinctly darker than water marks, often a deep grey shading toward black around the edges.
A few things worth knowing if you're dealing with this specifically:
- Prevention is genuinely the best approach, cleaning up accidents immediately reduces how deeply the reaction penetrates in the first place.
- A wood-safe oxalic acid bleach product, formulated specifically for this kind of staining, is worth trying on an existing stain before assuming it's permanent.
- If bleaching doesn't fully resolve it, a darker stain applied over the area can disguise what remains, though this only works if the rest of the floor is also being restained to a similarly dark tone.
- In the most severe cases, individual affected boards may need replacing rather than treated, if the discolouration genuinely can't be lifted or disguised.
The Rest Of The Prep, Briefly
We've covered the following in more depth elsewhere, but as a quick checklist:
- Equipment: hire a drum sander with continuous belt or sleeve loading and an edger from a genuine tool hire specialist, rather than assuming any general rental option will do, and get the machine and belt quantities sized properly for your room before you start.
- Room prep: clear furniture and valuables, cover windows and doorways with plastic sheeting, seal off HVAC vents, remove doors that open into the room, and secure any loose boards before sanding begins.
- Belt changes: change sanding belts more often than feels necessary, a dulled belt keeps running without cutting deep enough to remove marks left by the previous grit, and this problem often isn't obvious until the finish is already applied.
Flawless Floor Sanding: Common Questions
Why does the base shoe need removing before sanding?
Both to protect the moulding itself from equipment damage, and because edger sanding slightly lowers the floor at the perimeter, which leaves the base shoe sitting awkwardly if it isn't removed and refitted afterwards.
Can pet urine stains really not be sanded away?
Often not fully, no. The chemical reaction between urine and the wood's tannins can penetrate deeper than standard sanding removes, unlike water stains, which usually disappear completely with a couple of sanding passes.
Is there anything that can fix a pet urine stain that won't sand out?
A wood-safe oxalic acid bleach product is worth trying first. If that doesn't fully resolve it, re-staining to a darker tone can disguise the remaining discolouration, or in severe cases the affected boards can be individually replaced.
How often should sanding belts actually be changed?
More often than feels necessary. A dulled belt can keep running without cutting deep enough to remove the previous grit's marks, and this often isn't noticeable until the final finish has already been applied.
Call us on 020 7036 0625 or request a free site visit if a stubborn stain or a full sanding project needs a professional hand.
