There is a moment in most window projects when a quote turns into a signed contract. That signature commits you to specs, money, and a timeline that can be hard to change later. Five minutes of careful reading at this stage saves a lot of friction down the road.
Here are the five things we tell people to verify on any sliding window contract before they sign, whether the contract is with us or someone else. Each one looks small. None of them are.
1. The glass spec is fully written out
The single most common reason two window quotes look different is that the glass spec is different. The cheaper contract sometimes quietly dropped from 1/4 inch tempered down to 3/16 inch clear, or from laminated down to standard tempered. By the time the install is done, you cannot tell from looking which spec went in.
A proper contract names the glass thickness in millimetres and the treatment (clear, tinted, frosted, tempered, laminated) for every single unit. If yours says “safety glass” with no number, or “premium glazing” with no detail, that is a hole in the contract that should be filled before you sign.
2. The hardware is named, not just called “quality”
The locks, handles, rollers, and brushes are where ten years of performance lives. A cheap roller fails in eighteen months. A good one is still smooth at year ten.
Your contract should specify the hardware brand or grade for the moving parts. If the contract says “standard hardware included,” ask which standard. If the contract names a hardware system (Yale, Schlegel, a specific extrusion brand) you have something to verify. If it does not, you are taking the installer’s word that whatever shows up on the day is what was priced.
3. The scope includes everything that happens on site
A window install is more than just the window. There is the removal of the old unit, the disposal of debris, the prep of the opening, the sealants, the trim, sometimes scaffolding for upper floors, and a final cleanup.
Read the scope section line by line. Confirm in writing that the following are included (or explicitly noted as not included, so you know to budget separately):
- Removal of the existing windows
- Disposal of the old units and any debris
- Interior and exterior sealants
- Trim and finishing around the new opening
- Scaffold or boom access if needed for upper floors
- Site cleanup after install
A “supply and install” line item with no scope detail leaves you wondering on the day why your contractor is asking for a skip rental at extra cost.
4. The warranty terms are in writing
Most reputable installers in Jamaica offer a workmanship warranty of one year. Some go longer. The warranty should be on paper, with three things spelled out: how long it lasts, what it covers, and what it does not.
A workmanship warranty typically covers the install itself, the seals, and the operating action of the windows. It usually does not cover damage from impact, settlement of the building, or improper cleaning. That is normal. What you want to see is that it is written down so there is no debate later about what was promised.
If the manufacturer’s warranty on the aluminum profile or the glass is separate, the contract should reference that too, with a copy attached if possible.
5. The payment schedule is staged, not lump-sum upfront
No installer should ask for 100 percent of the contract value before any work has started. That is the most basic protection both parties have.
The standard schedule in Jamaica looks like this. A deposit on signing to cover materials and start fabrication (commonly around a third to half of the total). A progress payment when units are delivered or at install start. The balance on completion after a walkthrough.
If your contract asks for full payment upfront, ask why. If your contract asks for less than 20 percent deposit on a custom job, that is also worth a question, because the installer will need money to buy materials before fabrication begins.
Things to ask about that are easy to skip
A few items are not strictly contract clauses but are worth confirming verbally and then noting in writing:
- Liability coverage during the work. Most reputable installers carry general liability. Practice varies in Jamaica and across trades. The meaningful protection is a real shop with a written warranty backed by an installer who will come back to fix issues. Ask what their cover is and how claims are handled.
- Lead time on fabrication. Stock units ship in days. Custom units run weeks. Get the expected install date in writing.
- Who actually does the install. Some contractors quote the job and sub the install to a different crew you have not met. There is nothing wrong with that, but you should know.
- Change order procedure. If the scope changes mid-project (because of site conditions discovered during removal, or because you decided to upgrade the glass), the contract should say how the price adjustment is handled and approved.
What we put on a sliding window contract
For full transparency, here is what we put on every written quote we send out: the glass spec by unit, the aluminum profile and finish, the hardware system, every line item of site work, the lead time, the install duration, the payment schedule, and our one-year workmanship warranty terms. Everything fits on two pages. Nothing changes without written approval from you.
That is the standard we recommend you hold every installer to, including us.
Red flags that should stop you from signing
A short list of things that should make you pause:
- A verbal-only quote with no written contract
- A contract with a single “supply and install” line and no spec or scope breakdown
- A demand for full payment upfront on a custom project
- No written warranty, or a warranty written so vaguely that it covers nothing specific
- An unwillingness to put any specific commitment in writing when you ask
Any one of these is solvable. Two or more, especially together, is a signal to get another quote.
Related reading
- What is included in a written sliding window quote
- How a one-year workmanship warranty works on sliding windows
Frequently asked questions
What should a sliding window contract include?
At minimum: the glass spec by unit (thickness and treatment), the aluminum profile and finish, the hardware system, every site work line item, the warranty terms, the payment schedule, and the lead time. A one-line “supply and install” total without breakdown is not a contract you can verify or compare.
Is it normal to pay a deposit for window installation?
Yes. The standard schedule in Jamaica is a deposit on signing to cover materials and start fabrication (commonly a third to half of the total), a progress payment when units are delivered or at install start, and the balance on completion after a walkthrough. Full payment upfront is a flag.
What is a sliding window workmanship warranty?
A workmanship warranty is the installer’s promise to fix any install defect that shows up within a defined period. The standard in Jamaica is one year on the installation itself. The warranty should be written in the contract with what it covers, what it does not, and how to make a claim.
Should I ask for proof of insurance from a window installer?
Most reputable installers carry general liability insurance. Practice varies in Jamaica. The meaningful protection is a real shop with a written warranty backed by an installer who will come back to fix issues. Ask about coverage and how claims are handled.
What is the most common mistake in window installation contracts?
Vague glass and hardware specs. “Premium glazing” or “quality hardware” gives the installer room to deliver the cheaper option without breaking the agreement. The fix is naming specific thicknesses, treatments, brand systems, and warranty terms in writing before signing.
The next step
If you are weighing quotes from multiple installers, the easiest comparison is a side by side of the spec lines, not the bottom line. The quote request form sends through to us with whatever scope detail you have. We come back with a written quote that lays the spec out the way this article describes, so you can compare apples to apples.
The sliding windows service page covers what we typically install. The contact page has WhatsApp and phone if you want to talk it through before getting formal quotes.
The right contract is the one where everything you cared about up front is still in writing the morning of install day.