In short
- A workmanship guarantee comes from the contractor and covers their installation.
- A product warranty or system guarantee comes from the manufacturer and usually requires their full system to be used by a trained installer.
- An insurance-backed guarantee protects you if the contractor stops trading.
- Get every guarantee in writing before work starts, with its length, cover and conditions.
The three types
| Type | Given by | Covers | Weakness |
|---|---|---|---|
| Workmanship guarantee | Contractor | Faults in installation | Worthless if business closes |
| Product or system warranty | Manufacturer | Product performance, sometimes system | Conditions on installer and system |
| Insurance-backed guarantee | Insurer | Contractor's guarantee if they cease trading | Scope set by policy |
What to ask
- Who issues each guarantee and for how long?
- What exactly is covered: cracking, de-bonding, colour fade?
- What is excluded: movement, lack of maintenance, damage?
- What maintenance is required to keep it valid?
- Is it transferable if you sell?
Your statutory rights
Regardless of any guarantee, the Consumer Rights Act 2015 requires services to be performed with reasonable care and skill. A guarantee adds to your rights; it does not replace them.
Reading a guarantee document
A useful guarantee names the property, the work carried out, the products used, the start date and length, what is covered and excluded, and how to make a claim. A one-line note on an invoice saying "10-year guarantee" gives you very little.
Common exclusions
- Structural movement of the building.
- Damage from impacts, alterations or other trades.
- Lack of maintenance, such as blocked gutters causing saturation.
- Natural weathering, minor colour change and organic growth.
- Hairline crazing within tolerances.
Insurance-backed guarantees
An insurance-backed guarantee (IBG) is a policy that steps in to honour the contractor's workmanship guarantee if the business stops trading. It does not usually cover everything: it typically mirrors the contractor's own guarantee. If one is offered, ask for the policy document, not just a certificate.
Deposit protection
Some schemes protect deposits so that, if the contractor fails before starting, you recover your money. It is worth asking whether this is available.
Keep the paperwork
Store guarantees with building control certificates and any planning decision. You will need them if you claim, and buyers' solicitors will ask for them when you sell.
Questions people ask
What is a typical render guarantee?
Contractors commonly offer workmanship guarantees of several years; manufacturer-backed guarantees on complete systems can be longer. Terms vary widely.
Does mixing brands void a guarantee?
Manufacturer guarantees generally require their complete system. Mixing components usually voids them.