It is important to contact the company as soon as possible if the double glazing develops a fault at any time during the guarantee period to arrange a repair before the fault worsens. Any repairs should be carried out within a reasonable period of time and without causing you significant inconvenience.
Hopefully, the fault is one that can be repaired easily by the company you purchased it from but if not, then you would be well within your rights to claim compensation. This would usually be the amount that it costs you to get another company in to complete the repair.
Ask about:
How long they've been in business;
If they'll repair it regardless of whoever fitted it;
Area covered;
If they're insurance backed;
If they offer a guarantee;
Call-out charges;
Do they repair misty units, hinges, conservatory leaks, locks, rollers, springs;
Do they do replacements;
Materials used.
In England / Wales all replacement window installations are subject to building regulation approval or in most cases are covered by the FENSA self certification scheme. FENSA is used by double glazing uk trade companies to certify that their replacement windows and doors installed comply with Building Regulations Document L (and more), actually checking on average 1% of all replacement windows installations.
