Window & Door FAQs

New design for PERFORMANCE triple glazed timber window range with new Accoya drip railGeneral

Which window range is the most suitable for my project?

Please ring us on 01484 463336 for advice on the best range for your project. See our summary and overview of the ranges.

How do I get a quote for windows and doors?

Please complete our online quote form or call the office on 01484 463336.

Does Green Building Store have an installation team?

Yes, we do! Our fitting service operates throughout the UK.

Does Green Building Store have a showroom where I can see the windows and doors?

Yes, we have a showroom in Huddersfield and a permanent exhibition at National Self Build & Renovation Centre, Swindon

Is Green Building Store exhibiting near me?

We do exhibit at a number of events throughout the year covering a wide geographical area, making it easier for customers to see our high performance triple glazed timber windows first hand.

Are Green Building Store’s windows inward or outward opening?

Our ranges can be inward or outward opening.

Does Green Building Store offer double and triple glazing?

Green Building Store’s windows and doors are triple glazed as standard.

What materials are Green Building Store windows made from?

Green Building Store windows & doors are all made from timber. Our ranges are made from FSC® certified Redwood or Oak. Modern timber finishes are now so durable that, for most applications, we recommend them over aluminium cladding or UPVC.

What other services do Green Building Store offer?

In addition to our triple glazed timber windows and doors, Green Building Store offers a wide range of products and services,  including advanced MVHR heat recovery ventilation, specialist airtightness & insulation products, and consultancy.

What is the guarantee on Green Building Store windows and doors?

We provide up to 10 years warranty on our range of timber window and doors. Speak to our team to find out more.

How long has Green Building Store been in business?

Green Building Store was set up in 1995, under the name Environmental Construction Products.

My project is close to the sea, is this a problem?

Green Building Store can provide marine grade hardware but have different warranties for extreme coastal locations, please speak to one of the team for more information.


What colour can I have my windows?

Green Building Store’s windows and doors are available in the RAL classic range and we also have a selection of natural wood stains to choose from.

Can I have a different colour inside to outside?

Yes, please specify this when requesting a quote.

Are Green Building Store windows and doors Part Q compliant?

Green Building Store windows and doors can be made Part Q compliant, please specify this when requesting a quote and our estimators can use your elevations and floor plans to ensure we comply with Part Q.

Are Green Building Store windows and doors Secured By Design compliant?

Green Building Store windows have an option to be SBD compliant, please specify this when requesting a quote.

Does Green Building Store offer sliding doors?

Yes, our Lift & Slide Doors have Class 4 airtightness with optional SBD/ Part Q security.

Can I have a cat-flap installed in my door?

Yes, we can include cat-flaps in fully glazed doors. Please note that the cat flap would be at least 300mm from floor level. Our doors all achieve the highest level of airtightness at Class 4, but adding a cat flap would obviously affect this. Cat flaps are not advised for Passivhaus builds unless you use a specialist Passivhaus-suitable cat-flap, which we can advise on.


Where can I download window and door section drawings?

You can download these on our technical page, if you are unsure please call one of the team and we can send these via email.

What is a U value?

U-Values measure how well heat is transferred by the entire window/ door – the frame, sash and glass – either into or out of the building.  The lower the U-Value number, the better the window or door will keep heat inside a building on a cold day.

Does Green Building Store have PHPP-ready data available?

Yes, we supply PHPP data on our windows and doors for those needing the information for Passivhaus projects. You can download our PHPP10 file on our technical page.

What about quadruple glazing?

Quadruple glazing is not energy or cost optimal in the UK climate zone.  Although the thermal transmission is reduced, so is the solar gain.  So on balance, this gives worse performance for the building at a significantly increased cost.  Triple glazing is at the ‘sweet spot’ of optimal energy balance while satisfying our need for warm inner surfaces to meet Passivhaus comfort criteria. In colder climates, quadruple glazing is required for optimal energy balance and warm inner surfaces.


Aftersales and Installation

Does Green Building Store have an aftersales team?

Yes, we have a dedicated Aftersales team with office and on the road staff. Please call our Aftersales Manager Emma Platt on 01484 463336 or email

Does Green Building Store supply fitting instructions?

Yes, these are sent out with each order.

Does Green Building Store supply adjustment instructions?

Yes, please contact the team.

Does Green Building Store supply maintenance instructions?

Yes, please see our Installation & aftercare page.

Do your locks satisfy insurance company requirements?

Yes, we use 3 star Brisant ULTION cylinders and our hardware is all multi point locking.


Affiliations & Accreditations