Frequently asked questions

We supply our windows and doors via a network of specialist window distributors. We refer our customers to a distributor depending on the area and individual requirements of their project.

All we need is the type of window (timber or timber with aluminium cladding), dimensions and a window schedule or drawings of the elevations if you have them.

Click here to get quote

The lead time depends on the requirements of your project. As a standard, we aim to achieve a lead time of 8-10 weeks from final sign off.

After we refer your details to one of our distributors, they will contact you within 48 hours. You will receive a quotation within 5-7 working days.

Rationel windows and doors have been tested and marked in compliance with several national and European standards, including "Secured by Design".
 
Read more about SDB here

Rationel offers windows and doors for all building styles and shapes.

Read more about the different series of products we offer

Yes, many of our approved nationwide distributors having showrooms.

Why not join us at an upcoming show?

If you wish to see our windows, don’t hesitate to contact us.

Rationel offer a wide range of standard colours.

See available colours for the Rationel FORMA and Rationel FORMAPLUS ranges

See available colours for the Rationel AURA and Rationel AURAPLUS ranges

You can read more about the maximum and minimum sizes of our different products here 

Learn more about the watertightness, wind resistance, and security capabilities of Rationel windows

No, unfortunately Rationel Windows are not CWCT certified, which is an Air permeability, watertightness, wind resistance and impact mandatory test for all curtain walling.

When tested through window/door frame section, the equivalent area achieved is 2224mm2. When tested through a generic board, the equivalent area achieved is 3786mm2. This figure can be applied all current Rationel window systems. 

Testing has been carried out according to EN13414-1.

The information printed on the spacer bar between the panes of glass has information about pane size, energy values, and the Rationel order and position number.

Here's an example of the text found in the panes spacer:

22-04-2011 83314 2659 / 24 EN 1279 2601013 Optifloat Clear 4mm/TGI RAL7035(18)/Argon/Optitherm S3 4mm 764x530 1254518 / 7 ENERG:A U=1,14 g=0,59 Lt=0,80

The amount of information found will depend on the age of the window. In newer windows you can find the information outlined above.

For any warranty issues please, contact us and advise the Rationel order and item number of your window or door.

If you have bought Rationel AURAPLUS or Rationel FORMAPLUS (timber/aluminium) the maintenance you need to do is very minimal, but you will get the best results if you make a habit of cleaning the external aluminium whenever you wash your glass.

For general information on how to keep your windows and doors clean and well adjusted consult the Rationel operation and maintenance manual.

While knots are just a natural result of aging woodwork, knots that bleed through the paint on your windowsill or other surfaces can be unsightly.

To treat knots, take a good quality, sturdy cloth – one that won’t fall apart or allow product to soak through to the skin – apply some all-purpose cleaning product that contains ethanol and then wipe lightly on the extraction, before rinsing it with clean water. Any resin that has crystallised can be removed with a stiff brush or scraped away.

If your painted surface has been damaged in the process, sand the area with fine sandpaper and repaint it with a soft brush or a smooth surface roller – touch up paint is available from from our stores department – contact them on 01869 388825 or email stores@dovista.com.

If you have condensation on the outer side of your window glass, this is actually proof that your window is very energy efficient, and that it is functioning properly.

During colder nights, you may find that the outer surface of your low-energy pane is colder than the air outside. This results in condensation on the glass surface. However, this dew will disappear when the air temperature rises during the day.

Condensation between the two pieces of glass is a sign that the sealed glass unit is punctured and should be replaced.

If you have condensation on the internal side of the glass, this means you will need to ventilate the room, as this is often a sign of relatively high indoor humidity. You should look to reduce this in order to prevent rot, moisture damage and a poor indoor climate.

Learn more about how to create a healthy indoor climate for your home

Glass labels on new windows can be removed by soaking them in water. Any label residue or glue left on the glass can be removed by gently applying ceramic hob cleaner.

Download the Rational Operation and Maintenance Manual

When installing it will in most cases be useful to separate frame and sash.

>>  In the Operations and Maintenance Manual you can read about separation of the frame and sash. Download here.

Subject to our terms and conditions, Rationel guarantees that the goods we supply will comply in all material respects with their specifications and be free from defects in materials and workmanship for a period of five years from the time that they are passed from Rationel to the customer.

It is also worth noting that our products are covered by a product liability insurance covering damages caused by them. This insurance applies if the damage is proved to be caused by a fault on the part of Rationel - it does not cover consequential loss, loss of profits or any other indirect loss.