Advice
Mastic and sealant advice
Practical guides from 20+ years of sealant work: what fails, why, and how to put it right.
Main guides
How Much Does a Mastic Man Cost? UK Guide
What affects the cost of resealing a bath, shower, kitchen or windows, with published UK price ranges and what a fair quote should include.
Read the guide →Mastic vs Silicone: What’s the Difference?
Mastic, silicone, caulk and hybrid sealants explained in plain English: what each one is for, where it fails and which one your job needs.
Read the guide →How Long Does Silicone Sealant Last?
How long bathroom, kitchen and window sealant usually lasts, what shortens its life, and the signs it is time to have it replaced.
Read the guide →Why Does Bathroom Sealant Go Mouldy?
Why black mould grows into bath and shower silicone, why bleach rarely fixes it, and how to stop it coming back after a reseal.
Read the guide →Can You Put New Silicone Over Old Silicone?
Why sealing over old silicone fails, what happens underneath, and how old sealant should be removed before a new bead goes on.
Read the guide →How to Reseal a Bath (and When to Call a Pro)
A step-by-step guide to resealing a bath properly, the mistakes that cause leaks and mould, and when a professional reseal makes sense.
Read the guide →Window Mastic: When to Replace It and How
How to tell when the mastic around your windows and doors has failed, what replacing it involves and which sealant suits each frame.
Read the guide →Leaking Shower? How to Tell if It’s the Sealant
How to work out whether a shower leak is the sealant, the tray, the screen or the plumbing, with simple checks you can do first.
Read the guide →Expansion and Movement Joints Explained
What movement joints in brickwork, render, floors and tiling are for, why they fail and how they should be sealed and maintained.
Read the guide →Sand Mastic for Sash and Case Windows
Traditional burnt sand mastic explained: where it is used on sash and case windows and stone, how it compares with silicone and how it is applied.
Read the guide →More advice
How Long After Sealing Can I Use the Shower?
Cure times for bathroom silicone, what happens if it gets wet too soon, and how to plan a reseal around the household.
Read the guide →How to Remove Old Silicone Sealant
The safe way to cut out and clean off old silicone from baths, showers and worktops without scratching the surface.
Read the guide →Can You Clean Black Mould Out of Silicone?
What works and what doesn’t when black mould gets into sealant, and when the only real fix is replacing the bead.
Read the guide →Sealing Kitchen Worktops, Sinks and Upstands
Where kitchen sealant goes, why water gets behind worktops, and how to keep the joints around sinks and hobs sound.
Read the guide →What Is Fire-Rated Sealant? A Plain Guide
Intumescent and fire-rated sealants explained: where they are used, why the tested detail matters and what to ask your installer.
Read the guide →New-Build Sealant Snags: What to Check
The sealant problems new-home owners find most often, how to report them, and what a proper snagging reseal involves.
Read the guide →Sealant Maintenance for Landlords and Agents
Why failed sealant causes damp, mould and leak complaints in rented homes, and how to keep it on top of it between tenancies.
Read the guide →Tenement Flat Leaks in Scotland: Sealant
How a failed bath or shower seal in a tenement flat can reach the flat below, and what to check before it becomes a dispute.
Read the guide →Scotland’s Weather and External Mastic
Why wind-driven rain and freeze–thaw are hard on window and door mastic in Scotland, and what lasts best on stone and harled walls.
Read the guide →Mastic on Granite and Sandstone Homes
How sealant behaves on Aberdeen granite, Glasgow and Edinburgh sandstone and other natural stone, and why the right product matters.
Read the guide →Coloured Sealant and Colour Matching
When white, clear, grey or coloured sealant looks best, how colour matching works and what to expect from each finish.
Read the guide →Regrouting or Resealing: Which Do You Need?
The difference between grout and sealant, which joints need which, and when a bathroom needs both done together.
Read the guide →Sealing a Wet Room: What Matters
Where sealant goes in a wet room, why the tanking underneath matters more, and how to spot a wet room seal that has failed.
Read the guide →Conservatory Leaks and Glazing Silicone
Common places conservatories leak, which leaks sealant can fix and which need a glazier or roofer instead.
Read the guide →Leaking Gutter Joints and Fascias: Can Sealant Help?
When a dripping gutter joint or fascia can be sealed, when parts need replacing, and how to tell the difference from the ground.
Read the guide →Sealing Between Floors and Skirting Boards
Why gaps open between floors and skirting, which sealant suits each floor, and when a gap is a sign of something bigger.
Read the guide →Sealant in Commercial Washrooms
How offices, schools and leisure sites keep washroom and welfare sealant clean and sound, and how to plan a programme of work.
Read the guide →Resealing Hotel Bathrooms With Less Disruption
How hotels can plan bathroom resealing room by room, keep rooms out of use for as short a time as possible and avoid repeat failures.
Read the guide →Could Old Mastic Contain Asbestos?
Why some older mastics and sealants can contain asbestos, which buildings are at risk and what to do before anything is disturbed.
Read the guide →Decorator’s Caulk vs Silicone: Which and Where
Why caulk and silicone are not interchangeable, where each belongs and how using the wrong one causes cracks, mould and leaks.
Read the guide →How to Choose a Mastic Man: 10 Questions
Ten questions to ask before you book anyone to reseal your bathroom, windows or commercial site, and what good answers sound like.
Read the guide →Looking After New Sealant: Aftercare Tips
Simple habits that help new bathroom and kitchen sealant stay clean, white and watertight for longer.
Read the guide →Hard Water, Limescale and Bathroom Sealant
How hard water in the South East and soft water in Scotland affect bathroom sealant and cleaning, and what to use on silicone.
Read the guide →