6-8 week supply only lead time

8-10 week supply & installation lead time

10 year warranty, 60 year life expectancy

Designed by you, made to measure by us

97% of our customers would recommend us

Whole window U-values as low as 0.8W/m2K

This guide has been designed to offer practical advice to help care for your new windows and doors and covers everything from delivery through to occupancy.

Our objective is to provide simple and valuable advice on how to control your storage environment, the installation process, and moisture content to make sure you take full advantage of the performance capabilities Bereco windows and doors have to offer.

The do's and don'ts from delivery to occupancy



  • Prepare a suitable storage area upon delivery.
  • Check your delivery is in accordance with your order, and report any damage or anomalies to Bereco within 5 working days.


  • Leave shrink wrapping on your windows and doors - this is for transport purposes only.
  • Carry any products in a horizontal position or by opening casements or glazing bars.



  • Store windows and doors in a dry, sheltered and well ventilated area to avoid dust and other contaminants.
  • Repackage (if necessary) in well ventilated, breathable packaging.
  • Store windows and doors off the ground on bearers.
  • Store all windows and doors in an upright vertical position to avoid distortion.
  • Take care while stacking products against finished surfaces ensuring all surfaces are protected.


  • Store your windows and doors outside where they are exposed to the elements.
  • Apply air tight or non-permeable packaging like polythene.
  • Store windows and doors in containers.
  • Store windows and doors in areas subject to condensation and very high temperatures.
  • Store your window and doors in areas subject to extreme temperatures.

During installation


  • Install windows and doors in accordance with Bereco’s Installation guide and PART L Building Regulations and the correct British Standards.
  • Install your windows and doors within 14 days of delivery.
  • Apply sealant around the window or door perimeter within 5 days of installation.
  • Apply Teknos Opti Joint V sealer approved to ISO 11600-F-25LM to all site coupled elements (e.g. cill extensions).
  • Ensure any cut or modified areas showing unprotected end grain are protected with Teknos water based products within your touch up kit provided.


  • Leave any unprotected end grain exposed to the elements as this may affect the long term performance of the timber.
  • Carry out redecoration works in environments below 5°C or in damp/wet conditions. Optimum conditions are between 5°C and 18°C.
  • Apply Teknos Opti Joint V sealant in environments below 12°C.

After installation


  • Make sure the property or building is heated and ventilated simultaneously.
  • Ventilate internal rooms that have undergone any plastering, screening or rendering to prevent swelling and raising of the grain.
  • Carry out any required adjustment of your windows and doors that may be needed due to environmental changes and settlement.


  • Apply any adhesive tape for finishing works (e.g. rendering).

Site Care and Storage FAQ's

What are Bereco windows and doors made from?

All our products are made from FSC® 100%, multi-layered, defect-free timber. Opposing grain direction applied during the engineering process, combined with removal of natural defects helps add significant strength to product sections.

How are Bereco windows and doors finished?

Our products are finished and protected by a Teknos factory finish system. Both are water repellent and flexible to expand and contract with the natural movement of timber. Teknos’ microporous finishes allow a natural transfer of moisture vapour between the joinery and the atmosphere

What are the most important factors you need to consider with storage and installation?

While protecting our factory-finished components from damage is well recognised, it is also vital that basic precautions are taken to prevent excessive change in the moisture content of the timber. In addition, it is essential that our products are installed level and plumb to 1/1000 degree in accordance with our Installation Guidelines and Part L of the Building Regulations.

Why is the installation process a fundamental part of your build process?

An incorrectly installed window or door cannot only affect the operation of our products but it can also have a negative effect on their performance capabilities. Cold bridging, significant air/heat leakage, and water infiltration are all potential issues that can arise from an incorrectly installed windows or doors. An incorrectly installed window or door would also invalidate any related warranties.

How does water affect our windows and doors?

The moisture content of timber changes constantly with variations in the ambient temperature and relative humidity. Excessive moisture content can cause dimensional changes through swelling or shrinkage of components, blistering, localised failure of the surface coating, bowing or twisting of the timber, cracking of glazing units and operational issues.

What is the recommended moisture content of our timber windows and doors?

The manufacturing process is carried out in a controlled environment, ensuring that all timber products are supplied at 12% (+/-2%) moisture content.

In typical UK conditions, timber dimensions will vary approximately 1% for every 3% change in moisture content. Our design allows for this movement, what it does not allow for is excessive moisture. Products that are fitted in an uncontrolled and unheated building site environment  means that the moisture content can increase up to and exceeding 25%. This can cause dimensional changes as large as 3-4% (which would equate to 2.5mm+/- in size causing windows and doors to stick and even not close).

The experts in timber windows and doors

Whether you’re a homeowner working on a renovation project for your home, an architect looking for specific windows and doors, or a trade professional building new homes and properties, we offer a tailored service to help you budget, design, and order bespoke timber windows and doors.


Want to get hands on?

Order corner samples of popular products including stain, ironmongery and bars delivered straight to your front door.

Order Product Samples

A really good company to deal with. Very helpful team of people from sales, technical support and delivery. Any time I called, I did not have to wait to speak to the right person and help was immediate. So not only great customer service but also terrific products, well designed and exact fit. Competitively priced.

Graham Roberts

I was very happy with Bereco’s service levels and the products are excellent, very good quality. I would have no hesitation in recommending them to others.

Simon Hazelton

Beautifully constructed windows which do the job perfectly. Handled Covid disruption effectively. Installation went smoothly. All in all a job very well done. Would recommend without reservation.


Visited the showroom last year and impressed with the finish and quality. Just as delighted with the windows and back door that we ordered. They look fabulous.


Our memberships & schemes

As a dedicated manufacturer of quality timber windows and doors, we are part of a number of specialist memberships and schemes. Check out the full list below.

The Anti-Greenwash Charter logo
ASBP logo
BlueSky Certification logo
FSC and Forests For All Forever
Secured by Design certificate
World Land Trust logo
Graphic of FENSA certificate

As seen in...

We’re pleased to announce our brand has featured in several national magazines and publications over the years. Here are some of the most recent places our products have been showcased.

The Times logo
Grand Designs Magazine logo
House and Garden logo
Homebuilding & Renovating logo
Construction Forum Magazine logo
Architects' Journal
Improve logo
Showhouse logo

Sign up to our newsletter.

Sign up to our mailing list and be kept up to date with our latest news, promotions and inspiration for your next project.