How Do You Choose a Window Contractor?
Most of what separates a good window job from a bad one is decided before anyone takes a window out. This page covers what to ask, what a clear estimate contains, and the answers worth paying attention to. Window Home Pros does not vet or endorse contractors, so these are questions for you to ask.
Licensing and insurance
Requirements differ by state and sometimes by municipality, so the first question is what applies where you live. Ask to see current proof of both licensing and insurance rather than taking the answer on trust, and check the dates. Insurance matters for a specific reason: if someone is hurt on your property and the contractor is not carrying cover, that can become your problem. This is a few minutes of checking before a job that will be in your walls for decades.
The two different warranties
There are usually two, and they cover different things. The manufacturer's warranty covers the window itself: the frame, the glass unit, the seals and the hardware. The workmanship warranty covers the installation, which is where most window problems actually come from, because a good window fitted badly will leak, draught and stick. A long manufacturer's warranty tells you very little about the quality of the fitting. Ask specifically what the workmanship warranty covers, how long it runs, and whether it transfers if you sell the house.
Who actually does the installation
Some companies employ their installers and some subcontract. Neither is automatically worse, but you should know which, because it affects who is accountable if something goes wrong and who the workmanship warranty is actually with. It is worth asking who will be in your house, whether the person measuring is the person installing, and who to contact on the day if there is a problem. Vague answers to those questions are worth noticing.
What a detailed scope includes
A clear estimate says what is being done, not just what it costs. Insert or full frame replacement. The make, series, frame material and glass package of each window. Whether interior trim and exterior capping are included. What happens if rotten wood is found in the opening, and how it is priced. How the openings are insulated and sealed. How long the job will take and how the house will be left each day. An estimate that is a single number tells you none of that, and it is the detail that makes two estimates comparable.
How payment is usually structured
A deposit when the windows are ordered, followed by payment on completion, is normal, because the windows are made to measure and the deposit covers the order. Being asked for the full amount before anything is ordered is not. It is worth agreeing in advance what triggers the final payment, and worth being clear about how any additional work, such as replacing a rotted sill, gets approved before it is carried out rather than appearing on the final bill.
Questions worth asking
How long have you been installing windows in this area. Can I see proof of licensing and insurance. Is this an insert or a full frame replacement, and why. Which make and series are you pricing, and what glass package. What happens if the opening has rot, and how is it priced. What does the workmanship warranty cover and for how long. Who will be in my house and is the measurer the installer. How are the openings sealed and insulated. None of these are unusual, and a contractor who does good work will have clear answers to all of them.
FAQ
Common questions
What should a window estimate actually include?
Whether each window is an insert or a full frame replacement, the make, series, frame material and glass package, whether interior trim and exterior capping are included, what happens if rot is found in the opening and how it is priced, how the openings are insulated and sealed, the expected timeline, and how the house will be left each day.
What is the difference between the two warranties?
The manufacturer's warranty covers the window itself against defects in the frame, glass, seals and hardware. The workmanship warranty covers the installation. Most window problems come from fitting rather than the product, so the workmanship warranty is usually the more important of the two to understand.
Should I be worried if a contractor subcontracts the installation?
Not automatically, but you should know. It affects who is accountable if something goes wrong and who the warranty sits with. Asking who will be in your house and whether the person measuring is the person installing is reasonable, and a clear answer is a good sign.
How much deposit is normal?
A deposit when the windows are ordered, with the balance on completion, is the usual arrangement, because the windows are made to measure. Being asked for the full cost before anything is ordered is not normal. It is also worth agreeing what has to be finished before the final payment is due.
Does Window Home Pros check or approve contractors?
No. Window Home Pros does not verify, vet, screen, license check or endorse any contractor. It connects a homeowner with one local window company, and the homeowner decides for themselves whether to go ahead. The questions on this page are there for exactly that reason.
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