Flat Roof Cost Calculator

Working out how much it costs for a new flat roof is now even easier than you think!

Using advanced technology Composite Roof Supplies have provided an easy 3 step solution for working out what you need and how much a GRP Roof Kit will cost. 

All you need to know is the Size of your roof! Its as simple as that, no experience is required.

Step 1: Step 1: The roof Length x Width: Enter the length and width in either Metric or imperial measurements.

Tip: if you have an L shaped roof create 2 separate kits just treat them as a square and a rectangle.

Step 2: The Roof edges: The Fibreglass edge trims are really important when the Grp is layed into position, the pre formed edge trim creates not only a nice finish but ensures water can run off the roof into any gutters or prevent water run off in sections where water must be contained. Note: If you have trims already select no trim required. 

The kit builder uses the standard size trims. seen in the section Step 3

Tip: you can add additonal trims or slighty different size trims within the shop section of the website here 

Fibreglass trims come in 3 different sizes the sizes below are excluded from the Flat Roof Calcualtor but can be purchased seperatley 

A170 drip trim – The smallest size of the dedicated drip trims, the dimensions are : Length 3m – Drop 65mm – Flange > 80mm – Roll 10mm - Compatible with the B230 raised edge trim

B230 raised edge trim – The smallest of the dedicated raised edge trims, the dimensions are : Length 3m – Visible face 105mm – Flange > 100mm – Roll 10mm

A250 drip trim – The largest of the drip trims, the dimensions are : Length 3m – Drop 140mm – Flange > 80mm – Roll 10mm - Compatible with the B300 raised edge trim

B300 raised edge trim–  The largest of the raised edge trims, the dimensions are : Length 3m – Visible face 175mm – Flange > 100mm – Roll 15mm

Fibreglass Trims Glossary

Kit builder Trim sizes:

A200 drip trim – The mid size of the drip trims, the sizes are : Length 3m – Drop 90mm – Flange > 80mm – Roll 10mm Compatible with the B260 raised edge trim

B260 raised edge trim– The mid size raised edge trim, the sizes are : Length 3m – Visible face 125mm – Flange > 100mm – Roll 10mm

Wall Edge - universal and has a flange of 100mm or 75mm - overal visible sections - 100mm x 25mm x 75mm - Overall height up the wall from the deck boards 125mm or 95mm

Flat Slope Trim - 300mm flat trim supplies rolled up up to 20metre pieces

Parapet Edges - 75mm x 105mm - internal or external 

Expansion Trim - used on roof over 50m2 or to join to roofs together like a felt garage and a new GRP Roof 

Step 3: Congratulations your GRP Kit is complete! you can add extras in the last step such as: