A garage roof quote that just says “replace garage roof – £X” isn’t enough. To compare roofers properly (and avoid surprise add-ons), you want a quote that lists exactly what’s included, from access and strip-out to edge trims, drainage, and waste disposal.
Use this checklist to review quotes for flat and pitched garage roofs.
The quick checklist (scan a quote in 60 seconds)
A good quote should clearly state:
- ✅ repair / overlay / full strip + replacement
- ✅ roof size (or what it’s based on)
- ✅ materials/system specification (not vague)
- ✅ edge trims + drainage details
- ✅ flashing/junction method (if attached garage)
- ✅ what happens to rotten decking/battens
- ✅ waste removal + disposal included
- ✅ timeline (start + duration)
- ✅ guarantee/warranty (what it covers)
- ✅ insurance confirmation
If 3–4 of these are missing, you’re not comparing like-for-like.
1) Scope: what exactly are they doing?
Ask the quote to state one of these:
Repair vs overlay vs full replacement
| Type | What it means | What the quote must say |
|---|---|---|
| Repair | Local fix | location of repair + method + what’s excluded |
| Overlay | New covering over existing | checks on deck condition + why overlay is suitable |
| Full strip + replace | Remove old roof and rebuild | strip-out method + new build-up detail |
Red flag: “overlay” with no mention of inspecting the deck/structure.
2) Measurements and assumptions
The quote should include:
- garage size (single/double) and/or approximate area (m²)
- roof pitch/type (flat / pitched)
- any assumptions (access, height, obstructions)
Why it matters: many “cheap” quotes assume easy access and a perfect deck.
3) Access and safety (often missing)
A proper quote should specify:
- access method (ladder, tower, scaffold)
- whether scaffolding is included (and cost if not)
- safe working approach for fragile roofs (especially asbestos cement)
Tip: If the garage is attached or access is tight, clarify this upfront.
4) Strip-out and disposal (make sure it’s included)
The quote should state:
- removal of existing roof covering (what exactly is being removed)
- disposal included (yes/no)
- where waste will go (licensed route where relevant)
If asbestos is suspected
Ask for:
- asbestos handling + disposal explicitly included
- whether they will treat it as non-licensed or NNLW (contractor decision)
- waste paperwork/notes provided
Red flag: “You dispose of the sheets yourself.”
5) Flat garage roof replacement: what must be in the quote
Flat roofs fail at edges and junctions more than the middle. Therefore, your quote should specify the full build-up.
A) Decking and structure
- inspection of existing deck
- replacement of any rotten/soft boards (with a price approach)
- new deck material type/thickness (if replacing)
- fixings method (as applicable)
B) The waterproofing system (specifics, not just “felt/EPDM/GRP”)
EPDM quote should include:
- membrane type (single piece if possible vs seams)
- adhesives/primers used
- perimeter fixing/termination approach
- outlets/drains and any pipework
Felt quote should include:
- number of layers (e.g., 2-layer/3-layer system)
- base layer + cap sheet type
- edge detailing method
GRP quote should include:
- deck prep and resin system
- trims and topcoat finish
- curing/weather limitations noted
C) Edge trims and falls (critical)
- drip edge/fascia trims included
- upstands at walls (if attached)
- how they will correct ponding or improve falls (if relevant)
- outlets/scuppers (if needed)
D) Wall junctions and flashing (if attached to house/party wall)
- termination detail at wall
- flashing approach (lead/other)
- whether they will chase/point (if lead flashing used)
6) Pitched garage roof replacement: what must be in the quote
For pitched roofs, you want clarity on the hidden layers.
Must include:
- tile/slate type (or “match existing” approach)
- underlay type (breathable membrane vs traditional felt)
- new battens (spec and treatment)
- ridge detail (re-bed/re-point vs dry ridge)
- verge detail (dry verge, mortar, or alternative)
- any replacement of broken tiles and fixings
- ventilation approach (if relevant)
Red flag: no mention of underlay and battens, just “new tiles”.
7) Gutters, fascias, and water management (the leak-makers)
A quote should state whether it includes:
- gutter clean, repair, or replacement
- downpipe checks/unblocking
- fascia/soffit repairs (if needed)
- confirming water runs into the gutter correctly
Many garage “roof leaks” start as drainage problems, so it’s worth including this.
8) Finishing, making good, and cleanup
Look for:
- sealing/finishing details around edges
- making good any disturbed pointing/render
- site clean-up included
- skip hire (if used) included
9) Warranty/guarantee and paperwork
A proper quote should include:
- warranty length
- what it covers (materials and labour)
- exclusions (blocked gutters, storm damage, lack of maintenance)
- payment terms and schedule
- VAT clarity
10) Variations: what happens if they find rot or hidden damage?
This is where costs creep in.
Ask the quote to confirm:
- how they price additional decking/batten replacement
- whether they’ll show photos before proceeding
- the hourly/day rate (if applicable) or fixed rates for common extras
“Must-have” quote line items (copy/paste list)
Use this as your own internal checklist:
Flat roof must-haves
- Full strip or overlay clearly stated
- Deck inspection + replacement allowance
- Waterproofing system detail (EPDM/GRP/felt)
- Edge trims/drip details
- Wall termination + flashing (if attached)
- Outlets/drainage and falls/ponding notes
- Waste removal + disposal
- Guarantee + insurance
Pitched roof must-haves
- Tile type/match approach
- Underlay + battens included
- Ridge system detail
- Verge detail
- Flashing/junctions (if relevant)
- Waste removal + disposal
- Guarantee + insurance
Copy/paste message to request a “proper” quote
“Hi, thanks for pricing the garage roof. Before I accept, can you confirm what’s included:
- Repair/overlay/full strip replacement?
- System spec (materials, layers/membrane, trims, outlets)?
- Deck/battens/underlay inspection and how you price any rotten timber?
- Edge trims/drainage details and how water feeds into gutters?
- Wall junction/termination/flashing approach (if attached)?
- Waste removal + disposal included (and asbestos handling if applicable)?
- Warranty (materials + labour), insurance, timeline and VAT?”
FAQs
Why do some garage roof replacement quotes look much cheaper?
Often because they assume an overlay, omit edge/junction details, exclude disposal, or don’t include timber repairs. Always check the scope.
What’s the most important detail for a flat garage roof quote?
Edge trims, drainage (falls/outlets), and wall termination details. A flat roof usually fails at edges before it fails in the middle.
Should a quote include guttering work?
Ideally it should at least include a gutter/drainage check. If gutter overflow caused the problem, you want that fixed too.
