Composite Door Measuring

25th August 2020

green composite door

When replacing a front door with a composite door, it’s important to get the measurements right, as each composite door is manufactured to the specific measurements of the opening.

And when it comes to measuring for the door, it’s not quite as straightforward as you might think. 

There are many variables to consider, each of which could affect the door’s functionality when installed. 

Things to bear in mind

  • When measuring, always measure the opening from brick to brick
  • Always measure the opening as viewed from the outside
  • Record measurements in metric, using mm 
  • Final measurements should include the sill and any additional items such as frame extenders

How to measure for a composite door

Because the size of your opening can fluctuate slightly along the height and width, it’s important that you get three measurements of each.

When measuring the width, get one measurement from the top, one from the middle and one from the bottom of the aperture. Then make a note of the smallest of the three.

Repeat this process for the height of the door, with a measurement of the right-hand side, left-hand side and middle of the opening. 

Reducing measurement to account for expansion 

You will need to reduce your measurements slightly to account for expansion.

Depending on whether you have a white or non-white uPVC frame, this adjustment will differ slightly. Reduce your measurements as follows: 

For White uPVC frames: 

  • Up to 3m – Reduce by 10mm
  • 3m-4.5m – Reduce by 15mm
  • Over 4.5m – Reduce by 20mm

For non-white uPVC frames: 

  • Up to 3m – Reduce by 15mm 
  • 3m–4.5m – Reduce by 22mm
  • Over 4.5m – Reduce by 28mm

Please note that the reduction should be made from the total width, and not taken from each side of the opening.

Once you have your measurements, you’re ready to order your composite door.

Looking for a trusted supplier of composite doors in Worthing? At MLI Building Products, we supply composite doors across Worthing and surrounding areas. Simply give us a call or drop us a message to see how we can help.

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Peter Hughes profile picture
Peter Hughes
2 years ago
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Davyd Oddy
3 years ago
Great service and products from super friendly staff. Specials thanks to Loretta and Stephen
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Stephen Gale
4 years ago
Great service good bunch lads
Response from the owner
4 years ago
Thanks Steve.
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4 years ago
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Kimberleyjanep
4 years ago
So helpful - Steve was so patient while I chose my new front door - which was installed by PBM Exteriors who recommended MLI. I cannot emphasise how much my new and very contemporary front door makes the house look so modern and 'new'. Just huge thanks for great service and an amazing grey anthracite grey front door and side panels!
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Response from the owner
4 years ago
You were very welcome Kim. It was our pleasure.
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Elliott Prior
5 years ago
Response from the owner
5 years ago
Thank you Elliott
Richard Jones profile picture
Richard Jones
5 years ago
Great people to do business with!
Response from the owner
5 years ago
Thank you Richard.
So pleased I found MLI to supply the windows and doors for my property renovation, Excellent Prices, far more competitive than any other quote I had. Service from Steve & Loretta was amazing, nothing was too much trouble. Everyone compliments us on the fantastic windows. I highly recommend. Thank you so much
Response from the owner
6 years ago
Hi Penelope. Thank you very much. 👍🏻
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Nigel Alderman
7 years ago
Friendly efficient service
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4 years ago
Thank you Nigel.
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sohel isat
7 years ago
Used to go there for delivery
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4 years ago
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