How to Stop Water Getting Under Kitchen Cabinets — Plinth Sealing Strip & Kickboard Trim Guide (16mm & 18mm)
Water has a habit of finding its way into the worst places in kitchens and bathrooms. One of the most common problems is water disappearing underneath cabinets and soaking into the bottom edge of the plinth.
Over time this can lead to swollen MDF, peeling surfaces, trapped dirt and unpleasant smells. It also makes the whole kitchen look untidy, especially around sinks, dishwashers and utility areas.
A plinth sealing strip is one of the easiest ways to reduce water getting underneath cabinets. You may also see this called a kitchen plinth sealing strip, kickboard trim, plinth seal or kitchen plinth edge protector.
This guide explains how they work, what size you need, how to install them and which option is best for your kitchen or bathroom.
The full range of plinth profiles
Why Water Under Kitchen and Bathroom Cabinets Is a Problem
Most kitchen plinths are made from MDF or similar materials. Once moisture gets into the bottom edge, it can slowly cause swelling and permanent damage.
- Moisture can cause MDF plinth panels to expand and deform
- Dirt and crumbs build up underneath cabinets and become difficult to clean
- Trapped moisture may create unpleasant smells over time
- Repeated exposure to water can ruin the finish of kitchen kickboards
- Open gaps under cabinets make kitchens look unfinished
This is especially common around sinks, dishwashers, utility rooms and bathroom vanity units.
What Is a Plinth Sealing Strip? (Also Called Kickboard Trim or Plinth Seal)
A kitchen plinth sealing strip is a flexible PVC profile fitted to the bottom edge of a kitchen plinth or kickboard.
Once installed, the soft flexible lip sits against the floor and creates a barrier that significantly reduces water ingress underneath cabinets.
They are commonly used on:
- Kitchen kickboards
- Bathroom vanity units
- Utility room cabinets
- Commercial kitchens
- Retail cabinet bases
Plinth Sealing Strip vs Plinth Block Edge Profile
People sometimes confuse a plinth block edge profile with a plinth sealing strip.
A plinth block edge profile is mainly decorative and protects visible board edges. A plinth sealing strip is designed specifically to reduce water, dirt and dust getting underneath cabinets.
What's the Difference Between Plinth Seal and Silicone?
This is one of the most common questions.
Silicone can temporarily seal gaps, but over time it often:
- Goes mouldy
- Discolours
- Peels away
- Needs replacing
A fitted PVC plinth protector strip creates a cleaner and more professional finish while remaining removable if needed.
What Size Plinth Sealing Strip Do I Need? (16mm vs 18mm)
The most common UK kitchen plinth thicknesses are 16mm and 18mm.
MW Profiles sealing strips are designed to fit both 16mm and 18mm plinth boards securely.
If you're unsure which size you have:
- Remove one plinth panel
- Measure the board thickness using a tape measure
- Check whether it is 16mm or 18mm MDF
Some kitchens use deeper or non-standard plinth panels, especially in bespoke kitchens or utility spaces.
Can You Cut a Plinth Sealing Strip to Size?
Yes. The strips can easily be cut using:
- Scissors
- A Stanley knife
- A sharp utility blade
This makes them ideal for kitchens with awkward corners or custom cabinet layouts.
Plinth Sealing Strip Colours — Which to Choose
Choosing the right colour helps the sealing strip blend naturally into your kitchen.
Transparent Plinth Sealing Strip — Most Popular Choice
The transparent option blends into almost any floor and cabinet colour.
It is especially useful on uneven floors because the flexible lip remains less visible.
White Plinth Sealing Strip — For Light & Modern Kitchens
White works best with modern kitchens, white cabinets and light flooring.
Light Grey Plinth Sealing Strip — Contemporary Finish
Light grey is a popular choice for modern grey kitchens and contemporary interiors.
Black Plinth Sealing Strip — Dark Kitchens & Anthracite Kitchens
Black sealing strips work particularly well with darker cabinets and modern kitchens.
Available Lengths — 0.5m, 1m and 2.5m
Plinth sealing strips are available in:
- 0.5 metre
- 1 metre
- 2.5 metre lengths
A standard UK kitchen usually requires between 4 and 8 metres in total depending on layout.
Measure the full cabinet run before ordering and allow a little extra for cuts and corners.
How to Install a Plinth Sealing Strip — Step by Step
- Remove the existing plinth or clean the surface
- Measure the plinth length carefully
- Cut the sealing strip to size
- Push the strip onto the bottom edge of the plinth
- Reinstall the plinth panel
- Press the flexible lip gently against the floor
- Repeat for corners and joins
Expert tip: If your floor is uneven, the transparent version usually gives the cleanest finish because the flexible lip adapts naturally to small gaps.
Do You Need Any Tools or Adhesive?
No adhesive is required.
The strip is designed as a push-fit system, making it very DIY-friendly.
If you want to learn more about fixing methods, see our guide on: adhesive vs screw fixings.
Plinth Corners and Joining Strips
Internal and external corners can be neatly finished using a 45° mitre cut.
Some customers also butt-joint strips in less visible areas for a quicker installation.
Transparent profiles are often preferred for visible corners because joins are less noticeable.
Plinth Sealing Strip vs Alternatives
| Option | Pros & Cons |
|---|---|
| PVC plinth sealing strip | Neat, long-lasting, removable and professional finish |
| Silicone caulk | Cheap initially but may go mouldy and crack |
| Foam strip | Temporary solution that can peel away |
| No protection | Allows water damage and dirt build-up |
For a cleaner finish around worktops and walls, see our guide on: how to seal the gap between worktop and wall.
Where to Use Plinth Sealing Strips (Beyond Kitchens)
- Kitchen base units
- Bathroom vanity units
- Utility rooms
- Boot rooms
- Fitted wardrobes
- Commercial kitchens
- Retail cabinet bases
Many customers also match them with matching skirting boards when finishing a full renovation.
Updated 19 May 2026
The full range plinth profiles
