uPVC windows are low-maintenance, energy-efficient window frames made from unplasticised polyvinyl chloride, designed to resist rot, corrosion, and weathering.
The Spectus vertical slider combines perfect proportions, period details and traditional techniques. Both frames and sashes can be mechanically jointed, avoiding the ‘giveaway’ mitred weld of uPVC. Sash horns are part of the sash, not an afterthought.
Georgian bars are milled for a superb fit. Deep bottom rails and a choice of sashes give impeccable sightlines. Traditional box-sash dimensions, hardware, and glorious period colours – it’s enough to melt the heart of the toughest planning officer.
Woodgrain Finished Options
You can choose to have an authentic woodgrain finish, whether you choose white, black or an authentic wood colour. You can also specify white on the inside of your frames and a woodgrain on the outside.
Dual-colour is a popular choice and reflects traditional frames where the outside is painted a different colour to the interior, allowing for greater flexibility in interior decorating.
| 29 Colour Options |
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| Run-Through Horns | Plant-On (no Horn) | Locking Mech | Tilt Mech | Finger Pulls |
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| Gold (1 of 4 colour options) | ||||
We are experts at window and door replacements, along with the complete build of garden rooms, extensions, verandas, sky rooms and conservatories. Let us know what you’re after and we will arrange a site visit at a convenient time for you, discuss your ideals and then give you a full, free, no-obligation quote for everything involved.
Got a question? Just ask – our advice is free.
uPVC windows are low-maintenance, energy-efficient window frames made from unplasticised polyvinyl chloride, designed to resist rot, corrosion, and weathering.
They offer excellent insulation, low maintenance, long life, and great value, making them one of the UK’s most popular window choices.
Quality uPVC windows typically last between 25 and 35 years with proper care.
Modern uPVC frames are UV resistant and retain their colour for many years with normal maintenance.
Yes. uPVC windows are available in many colours and woodgrain finishes.
Yes. Flush window styles and Woodgrain foils replicate timber without the upkeep.
No. They only require routine cleaning.
Clear, obscure, laminated, toughened, and acoustic glass are available.
uPVC requires less maintenance while offering excellent energy efficiency and durability.
UPVC Frames come with a guarantee of 10 years.
Consider energy efficiency, security, style, and budget. KRB expertise will help guide you.
PAS 24 is an enhanced UK security standard which ensures that external doors and windows resist physical attacks by opportunistic burglars. It features a pass-or-fail test system and helps satisfy Building Regs Part Q as well as the police-backed Secured by Design accreditation.
A U-value measures how well a building part (such as a door or window) lets heat pass through it, with lower numbers meaning better insulation. It is measured in Watts per square metre Kelvin (W/m2K).
FAQ content