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Doors for your home - DIY Tip 28


Note: Accurate measuring and cutting is required when you fit a door, please refer to the DIY Pages for further advice. If you lack DIY experience it is advisable to ask someone experienced to assist you.




PVCu doors; It is essential that you measure the inside of the overall opening at the top, middle and bottom, then check the height. This type of measuring should then be repeated from the outside (we normally remove the existing timber architrave/facings to allow us to see behind the timber door frame, assuming you are replacing a timber door with a pvc equivalent) and only then can you make an informed judgement on which combination of sizes will allow the pvc door - which comes with its own frame - to fit.

At this point we would advise that you take a total of 6mm from the width and height to give some fitting tolerances. it is not uncommon to have to make the pvc door/frame smaller to ensure it can fit. Timber packers can be fitted behind the frame to take up any clearance if you make this choice, which can then be concealed with facings.

Note, a pvc door will need to be "toed & heeled", this means that you will (no matter what a spirit level may tell you) have to adjust the hinges on the Horizontal, Vertical and Lateral planes, the lateral plane is that which allows you to move the door sash (the opening part of the door) away from or nearer to the fixed door frame. Any doubts, ask for advice.




Timber doors and/or frames, you will need to check that your door is or can be one of our standard sizes which are regularly used, if it is not, either refer to your preferred choice of door within our web site, email for advice on altering the standard door to size or choose to purchase a made to size Bespoke door.             

We can, in most cases, offer an alternative idea before you go to the expense of buying a bespoke door. The standard sizes we use for exterior doors are numerous; please refer to our web site.

You can in most cases cut solid timber Exterior doors to fit a smaller size opening by up to 20mm (3/4") from each of the four edges. Please allow the new door to sit somewhere dry overnight to acclimatise. Do not stand the door against an external wall as this can encourage it to twist or bow. Try and decorate the door before fitting and choose a dry day to fit it.


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Measuring doors and Frames; When measuring either your interior or exterior door, ignore the current door size and follow this advice and any relevant advice offered throughout our DIY pages.

Width: Measure each door between the frame at the top, the middle and the bottom.

Tell us or choose a door(s) to suit the widest size. Always remember that you are responsible for making sure that the widest size can be adjusted by you to suit the narrow area of any part of the opening without compromising the stability or affecting the look of the door.

Height: Measure from the carpet/floor covering to the underside of the timber lintol.  

Thickness: Now and only now do you measure the door to find out how thick it is at present. With interior doors you may have to compromise and fit a slightly thinner door - this does not normally present any problems.

REMEMBER WHEN MEASURING FRAMES; The above advice may be different if ordering a door and frame, so always check the overall outside sizes of the frame against the overall inside sizes of the frame and choose the correct combination of those sizes to suit the opening and ensure the frame will go in to the opening. This may involve you ordering a frame that is slightly smaller than the current frame. Now measure the frame breadth, ie; from the inside face to the outside face. You can always add a sub frame or concealed plates to make a frame fit the width or height but it can be very difficult and sometimes impossible to adjust the frame if you have ordered it too big.

Beware: Do not assume all interior doors in your house are the same size or thickness, check them all.


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