Firrings Price Calculator

We cut our firrings from timbers to your bespoke sizes. Their purpose is to form a slope or taper on flat roofs to make sure the rain water runs off. They are fastened, using nails, to the top of existing joists and then sheeted over. See the diagram below which illustrates the general shape of a firring. We stock an off the shelf firring that may work out cheaper. Please "click here" to view.

As a guide for deciding on firring height a minimum gradient of 80:1 is usually required. Using the drop down menus below please choose from our standard heights and gradients or enter your own heights and gradient. You can collect your firrings or have them delivered. The maximum firring length we can provide for collection is 12m. We are restricted to 11.4m firring length if we are delivering. For help on how to use this calculator go to the bottom of the page.

Enter your requirements

Quantity of firrings: 


Timber thickness:  

Timber treatment:  

Fall Option:   Which gives a gradient of 97:1.

Pricing table

Quantity Length Thickness Fall Gradient Weight Firrings Price Delivery Price.
(If required.)
2 firrings with a fall of 36mm to 5mm
over a length of 3000mm
cut from 1 pieces 3000mm
of 2"x2" nominal(untreated).
These firrings are 44mm thick.
2 pieces
3000mm 44mm 36mm to 5mm
(Note: These sizes are not exact
and are usually to within 2mm.)
97:1 3 kg £17.03 £20
Plus surcharge,
if applicable.
See map below.

If you want to place an order please copy and paste the pricing table above into an email and send it to us at where we will organise payment. If you require delivery please include your address. See below for additional delivery surcharges. We deliver the next working day on a non-guaranteed delivery service if you have placed the order before 9am. We cannot give a time of delivery as it is an all day appointment from 7am till 6pm. Please "click here" for terms of this delivery service. Alternatively, you can come into store to pay and wait for us to cut them. It usually takes up to 30mins depending on how busy we are. However, please ring to make sure we have a wood machinist available to do your order before you set out.

Delivery Surcharge Map

The map below is colour coordinated to additional delivery surcharges for your area.

Courier surcharge map

No surcharge-

No surcharge.-

No surcharge.-

Plus £10 surcharge.-

Plus £25 surcharge.-

Plus £50 surcharge.-

Uncoloured sections are to be quoted for.-

Calculator Help and Information

Quantity of firrings

When we cut firrings from our stock timbers we get 2 firrings per piece. If you order an odd number we will charge you for the next even number up. If delivery is needed then it would be cheaper to order exactly what you need as delivery cost is based on weight. The spare firring would be discarded in this case.

Length of firring

We will cut to length but we will charge for the nearest stock length. Our stock lengths are 2.4m, 3.0m, 3.6m, 4.8m and 6.0m which may vary depending on what section you require. Firrings less than 4.8m they will be supplied one piece. Firrings greater than 4.8m will be supplied in two halves

Timber Thickness

There is no structural reason why 69mm should ever be used for a flat roof but we have included it anyway in case matching up to 69mm joists is desired. Delivery will cost more for the 69mm due to increased weight.

Timber Treatment

Treatment of firrings is not needed for flat roofs but we have included it just in case it has been insisted upon. Treatment is only available in the 44mm thickness. WARNING: treatment will be cut away from the tapered edge and maybe from the bottom edge as well.

Fall Option

When choosing your "Fall option" below please note we have a far greater range of timber sizes to use in the 44mm thick firring option which could result in less waste and cost.