Door Frame Calculator

Lining timber lengths, architrave LM, threshold, and fixings - calculated per door with standard size presets.

Door type

Lining material

Lining width / depth (mm) Should match wall thickness + plaster both sides. Typical: 95 - 133 mm for 100 mm stud, 145 mm for 140 mm stud.

Lining thickness (mm) Typically 25 mm for softwood, 18 - 22 mm for MDF.

Waste / overage (%)

Include architrave Architrave both sides of every door. 2 verticals + 1 head per side.

Architrave width (mm) Face width: common 57, 69, 90 mm.

Architrave stock length (m)

Include threshold / sill bar Typically needed for external doors and room changes in floor type.

Include door stop beading Stop bead nailed to lining - 2 verticals + 1 head per opening.

Stop bead stock length (m)

Standard size presets click to populate a door below

Doors

Job Costing (optional)

Lining per LM Or use kit price per door below.

Lining kit per door overrides per-LM

Architrave per LM

Stop bead per LM

Threshold each

Fixings per door

Labour per door

Delivery (flat fee)

Results

Doors
-
openings

Lining to buy
-
linear metres

Architrave to buy
-
linear metres

Stop bead to buy
-
linear metres

Material List

Door Breakdown

Door / location	Opening (W×H)	Lining LM	Arch. LM	Stop LM	Threshold

Standard Door Sizes by Region

🇬🇧 UK

Size (mm)	Use
686 × 1981	Internal 2'3" (older)
762 × 1981	Internal 2'6" (common)
838 × 1981	Internal 2'9"
762 × 2040	Internal metric
914 × 2134	External 3'0" × 7'0"
1000 × 2100	External metric

🇺🇸 US / Canada

Size (mm / inches)	Use
762 × 2032 (30"×80")	Internal - common
813 × 2032 (32"×80")	Internal - standard
914 × 2032 (36"×80")	Internal / ADA
914 × 2134 (36"×84")	External - standard
1016 × 2134 (40"×84")	External - wide

🇪🇺 Europe

Size (mm)	Use
700 × 2000	Internal - narrow
800 × 2000	Internal - standard
900 × 2100	Internal / External
1000 × 2100	External - standard
1200 × 2200	External - wide

🇦🇺 AUS / NZ

Size (mm)	Use
820 × 2040	Internal - standard
870 × 2040	Internal - medium
920 × 2040	Internal / External
1020 × 2040	External - wide

All sizes are opening (rough opening) dimensions. Lining opening is typically door size + 6 - 10 mm each side + 10 mm head clearance.

Lining Depth Guide

Wall construction	Lining depth
75 mm stud + plaster both sides	95 - 108 mm
100 mm stud + plasterboard both	112 - 120 mm
100 mm stud + 12.5 mm pb both	125 mm
140 mm stud + pb both sides	165 mm
100 mm block + plaster	120 - 133 mm

Fitting Notes

Lining = 2 jamb legs + 1 head piece. Jambs run full height; head sits between.
Architrave = 2 legs + 1 head per side of door lining. Mitre at top corners.
Stop bead = 2 legs + 1 head per door; 12 mm set-back from face of lining.
Check openings are plumb and square before fitting - pack out if needed.
Fix lining to studs with screws through plasterboard or directly to masonry with frame fixings.
Leave 2 - 3 mm between door leaf and stop for easy operation.
Pre-prime all cut ends of MDF before fitting.

Door Frame Calculator