How to Waterproof a Shed Roof
A well-maintained roof is essential for keeping your shed dry. Because it is constantly exposed to the weather, the roof is one of the most common places for leaks to develop. This guide explains how to waterproof your shed roof and keep it protected year after year.
Note: This guide applies to wooden sheds with felt or shingle roofing.
Why Shed Roof Waterproofing Is Important
If water gets through the roof, it can:
Cause damp and mould inside the shed
Lead to rotting timber
Damage tools, furniture, or stored items
Shorten the lifespan of your shed
Regular maintenance and early repairs can prevent costly damage later on.
What Is the Best Way to Waterproof a Shed Roof?
The most effective and affordable way to waterproof a shed roof is by using roofing felt, particularly green mineral roofing felt. This provides a durable, water-resistant barrier that protects the roof from rain, frost, and UV damage.
For sheds with shingle roofs, maintaining and replacing damaged shingles is equally important.
How to Waterproof a Shed Roof
1. Check the Roof Condition
Before adding or repairing any roofing material:
Inspect the felt or shingles for tears, lifting edges, or bald patches
Pay close attention to the ridge line and edges
Check inside the shed for any signs of damp or dripping
If the roof structure itself is damaged, this should be repaired before waterproofing.
2. Repair or Replace Roofing Felt
If your shed roof has felt:
Small tears or loose sections can be repaired using roofing felt adhesive or sealant
Severely worn or damaged felt should be fully replaced
When fitting new felt:
Start at the bottom edge and work upwards
Overlap sections to allow water to run off
Secure with felt nails at regular intervals
3. Maintain or Replace Roof Shingles
If your shed has shingles:
Replace any cracked, missing, or loose shingles
Use waterproof sealant for minor repairs
Ensure all shingles lie flat to prevent water getting underneath
4. Seal the Edges and Ridge
The edges and ridge of the roof are common entry points for water.
Check that ridge felt or capping is firmly in place
Apply waterproof sealant where necessary
Make sure all fixings are secure
How Often Should I Check My Shed Roof?
We recommend checking your shed roof at least once a year, ideally before winter. You should also inspect it after severe weather such as strong winds or heavy rain.
Extra Tips to Keep Your Shed Roof Waterproof
Keep nearby branches trimmed to prevent damage
Clear leaves and debris from the roof regularly
Ensure guttering (if fitted) is free-flowing
Avoid placing heavy objects on the roof
When Is It Time to Replace the Roof Covering?
You may need to replace your roof covering if:
Felt has become brittle or cracked
Shingles repeatedly lift or fall off
Water continues to enter despite repairs
Replacing the roof covering promptly will help prevent further damage to the shed structure.