Supplied and fitted across the UKFree surveyWritten fixed quoteGuide prices published0800 088 6248

uPVC windows · Hertfordshire

Triple glazed uPVC windows in Harpenden

If you live in Harpenden (AL5) and want triple glazed uPVC windows, start with a free survey: every opening measured, then a written quote that fixes the price.

AL5Postcode district
1.4U-value limit, England (W/m²K)
7h 46mDaylight, 21 Dec
15°Midday sun, 21 Dec
White uPVC casement windows on a 1930s red-brick semi-detached house

A way to triple glaze a whole house without the timber or aluminium premium. Triple glazed uPVC windows are plastic-framed windows fitted with a sealed unit of three glass panes and two gas-filled cavities.

Winter light and glass choice in Harpenden

On the shortest day, Harpenden gets about 7 h 46 min of daylight and the midday sun reaches only about 15° above the horizon. Low winter sun means north-facing rooms here gain little solar heat, which is where triple glazing’s lower heat loss helps most.

Guide prices in Harpenden

GuideSupply and fit, inc VAT
Small window
about 600 x 1000 mm (bathroom, landing)
£695 – £845
Medium window
about 1200 x 1200 mm (bedroom)
£895 – £1,095
Large window
about 1800 x 1200 mm (lounge)
£1,395 – £1,695

Guide prices. Your written quote after the free survey fixes the price for the specification shown.

Rules for uPVC windows in England

The rules for replacement windows in England are set by Approved Document L (2021 edition, with 2023 amendments): 1.4 W/m²K, or a Window Energy Rating of band B or better. Replacement windows are a controlled fitting. A competent person scheme installer (such as FENSA or Certass) self-certifies the work and notifies the council within 30 days; otherwise a building control body approves it.

Before ordering: Replacing windows on a house is normally permitted development if the new ones look similar. New upper-floor windows in a side wall must be obscure glazed and fixed, or open only above 1.7 m. Flats and maisonettes have no householder permitted development rights, so a change that alters their appearance needs planning permission. An Article 4 direction in a conservation area may mean permission is needed, and listed buildings need listed building consent.

How it works

You will know exactly what you are buying: the quote states the unit build-up, frame, finish, fitting work and how Building Regulations compliance is handled. On fitting day each opening is replaced and closed up before the team moves on.

  • Every opening measured, including escape and vent needs
  • Frames rated for the weight of triple glass
  • Old windows removed and taken away
  • Each opening closed up the same day

Questions from Harpenden

Will triple glazed uPVC windows look bulky?

The frames look much the same as good double glazed uPVC. The glass unit is thicker, but that sits inside the frame, so from outside the difference is hard to spot.

Do I need trickle vents?

In England and Wales, if your old windows had trickle vents, the new ones must have vents at least as big, and if they did not, the room must be no less ventilated than before. Scotland and Northern Ireland also require that replacement windows do not make ventilation worse. We size vents on the survey.

Do I need permission for triple glazed uPVC windows in Harpenden?

In England, like-for-like replacements on a house are normally permitted development; flats need permission if the change alters their appearance, Article 4 areas may need permission, and listed buildings need listed building consent. Check whether your street is in a conservation area or covered by an Article 4 direction before changing the style.

Do you fit triple glazed uPVC windows in Harpenden?

Yes. We arrange surveys and fitting in Harpenden and across Hertfordshire. Send your postcode and the windows or doors you want replaced, and we will book a free survey.

Nearby

We also cover nearby St Albans (8 km), Luton (8 km), Hemel Hempstead (10 km) and Welwyn Garden City (10 km).

Other products in Harpenden

uPVC windows in Harpenden: book your free survey

Written quote fixed for the specification, after a free survey. Building Regulations sign-off by a competent person scheme installer or building control, as the law requires in England.

CallGet a quote