This sizing guide for roof rafters will help determine what you need for your small project.
Roof truss sizes uk.
The truss is a framework consisting of rafters posts and struts which supports your roof.
We usually opt for the 35mm thickness in timber when designing standard roof trusses.
The important point to keep in mind when you use your truss calculator is that every truss calculation is completely unique and is based on the size of your roof and its specific dimensions.
The standard roof truss used for the majority of new build houses across the uk.
Add it to the square of the result obtained in step 2.
All truss images are for visual aid only and may not truly represent the roof truss supplied or designed by your chosen supplier.
Trusses must be designed for any special loading such as concentrated loads from hanging partitions or air conditioning units and snow loads caused by driftingnearparapetorslide offfromhigherroofs.
The following tables give details of the allowable spans and spacing for some of the more common timber sizes used in traditional roofing construction.
These trusses can also be used for garages and extensions as well as self build projects.
These trusses are designed as attic style with larger sections of timber to support additional loadings which allow people to live within the truss zone.
35mm standard roof truss.
01706 212 238 northern 01785 282 833 midlands northern office.
Spans for 2x4 top chord trusses using sheathing other than plywood e g.
Adding 4 41 ans 1 44 gives 5 85 and the square root of 5 85 is 2 42 8 06 feet.
Meanwhile the 46mm thickness option is used for attic trusses due to fire regulation guidelines.
To use the truss form existing roof dimension calculator.
Multiply multiply 2 1 by 2 1 to get 4 41 and 1 2 by 1 2 to obtain 1 44.
A gambrel room in attic truss also provides extra living space while giving your roof a barn like appearance.
The tool will calculate the missing field.
Pitched roof timber sizes.
Enter your existing heel size or rafter size.
There are several variables to consider when determining the proper rafter size.
These trusses are used when habitable space is required within the room zone.
Weather you re building a shed roof or adding a dormer to your second story it is important to choose the proper size rafter.
Square the result obtained in step 1.
Spaced sheathing or 1x boards may be reduced slightly.
All the figures are based on roofing tiles or slates laid on timber laths over sarking felt.
This could be for fink trusses in a house construction or queenpost trusses for a garage.
600 timber thickness mm.
The room size will vary depending on the width and slope of the truss.
To find out more about our roof trusses call our team on.
Gable room in attic trusses provide an economical way to add extra living space to your home or garage.