A garage roof quote can look straightforward: “repair” or “replace”, a price, and a start date. However, the details behind that quote determine whether the roof lasts 2 years or 20.
This checklist gives you the best questions to ask before you accept, plus what you want to hear in the answers. You can copy/paste the mini template at the end to send to contractors.
Start with the big picture questions (so you compare quotes properly)
1) “Exactly what’s included in the price?”
You want the quote to spell out:
- removal of old materials (and whether disposal is included)
- materials and system specification
- edge trims, flashings, outlets, guttering
- any insulation/board upgrades
- access equipment (tower/scaffold)
- making good (fascias, verge, pointing if relevant)
- VAT (if applicable)
Why it matters: “replace garage roof” can mean anything from a quick overlay to a full strip and rebuild.
2) “Is this a repair, an overlay, or a full strip and replacement?”
Ask them to choose one and explain why.
What the options usually mean
| Option | What it means | When it’s OK |
|---|---|---|
| Repair | Local fix to the problem area | roof is otherwise sound |
| Overlay | New covering over an existing roof | only if the base is sound and dry |
| Full strip + replace | Remove old covering, rebuild properly | best long-term solution when roof is tired/leaking |
Red flag: a cheap overlay offered without checking the deck/structure.
3) “What’s the main cause of the leak, and where is the entry point?”
A good roofer should describe:
- where water gets in
- how it travels (tracking behind fascia, along a wall junction, etc.)
- what they will change to stop it
Why it matters: garages often “leak” due to gutters, downpipes, or wall junction flashing, not the main roof surface.
Questions that separate a “proper job” from a quick patch
4) “What materials and system are you quoting for?”
Ask for the exact system, not just the label.
Examples of what you want to see
- EPDM: membrane type, adhesives, trims, outlets
- Felt: number of layers, mineral finish, edge details
- GRP: decking prep, resin system, trims, topcoat
- Pitched tiles: tile type, battens, underlay, ridge/verge approach
Why it matters: “felt roof” can mean very different quality levels.
5) “How will you deal with the roof edges and drainage?”
This is where many garage roofs fail.
Ask:
- “How will water run off into the gutter?”
- “Will you install/replace drip edge or fascia trims?”
- “Are outlets/downpipes clear and sized correctly?”
Good answer: they talk about drip edge, falls, outlets, and gutter condition.
6) “Will you check the deck/structure underneath?”
For flat roofs, this is crucial.
Ask:
- “Will you inspect the decking for rot or softness?”
- “Will you replace any damaged boards?”
- “Is the roof currently ponding (standing water), and will you correct falls?”
Why it matters: a new covering over a weak deck often fails early.
7) “How will you handle flashing and wall junctions?”
If the garage meets a house wall, party wall, or parapet, ask:
- “How will you terminate the roof covering at the wall?”
- “Will you replace or repair lead flashing?”
- “Will you chase/point the flashing properly?”
Good answer: they explain termination detail, not “seal it”.
8) “What happens if you find extra damage once you start?”
This is a common scenario with old garage roofs.
Ask:
- “How will variations be priced?”
- “Will you show photos before extra charges?”
- “What are the likely extras (decking, fascias, gutters)?”
Why it matters: it avoids surprises mid-job.
Practical checks (quality, safety, and accountability)
9) “Are you insured, and what does it cover?”
Ask for:
- public liability insurance
- confirmation it covers roofing work
10) “Who will actually do the work?”
If you’re using a platform or network, confirm:
- is it the same team quoting and installing?
- do they subcontract?
- who is responsible for snagging and warranty issues?
11) “What guarantee/warranty do you provide — and what does it exclude?”
Ask:
- duration (e.g., 5, 10, 20 years depending on system)
- whether it covers materials + labour
- exclusions (storm damage, blocked gutters, lack of maintenance)
Tip: get it in writing.
Asbestos-specific questions (only if relevant)
If you suspect asbestos cement sheets:
12) “Have you allowed for asbestos handling and disposal?”
Ask:
- “Is asbestos waste packaging + disposal included?”
- “Will you assess whether it’s non-licensed work or NNLW?”
- “What method will you use to minimise breakage and dust?”
- “Will you provide waste paperwork/notes?”
Red flag: “You can dispose of it yourself.”
The “quote comparison” table (use this to compare contractors)
Use this table as your scoring sheet.
| Question area | Contractor A | Contractor B | Contractor C |
|---|---|---|---|
| Repair vs overlay vs full strip clearly stated | |||
| Materials/system specified (not vague) | |||
| Edges/drainage detail explained | |||
| Deck/structure inspection included | |||
| Flashing/wall junction method explained | |||
| Disposal and waste included | |||
| Insurance confirmed | |||
| Warranty in writing | |||
| Variations process explained |
Copy/paste message to send to roofers
Use this to get clearer replies quickly:
Message:
- “Hi, thanks for the quote. Before I accept, can you confirm:
- Is this a repair, overlay, or full strip + replacement?
- What exact materials/system are you using (including trims/outlets)?
- How will you detail the roof edges and drainage into the gutter?
- Will you inspect/replace any soft decking or damaged battens/underlay?
- How will you handle wall junctions/flashing (if applicable)?
- Is removal and disposal included (and asbestos handling if relevant)?
- What warranty do you provide (materials + labour), and what’s excluded?
- Are you insured for roofing work, and who will complete the job?”
FAQs
Why do garage roof quotes vary so much?
Because “replacement” can mean overlay vs full strip, material quality differs, and edge/drainage details can be included or skipped. Access and disposal also change costs.
Is the cheapest quote usually a bad idea?
Not always, but it often leaves out key items like edge trims, decking repairs, or proper junction detailing. Use the checklist to confirm what’s included.
What’s the single most important technical detail to ask about?
For flat garage roofs: deck condition + drainage (falls/outlets) + edge trims. For pitched roofs: underlay/battens + ridge/verge details.
