Safe Roof Access To Work
Is there adequate access to area of house to mount scaffolding or ladders?
(yes/no)
Is there steady and secure base on which to mount scaffolding or ladders?
(yes/no)
Are the scaffolding and or ladders fit for use intended?
(yes/no)
All installers trained in working at heights?
(yes/no)
Are all harness and other safety equipment working correctly?
(yes/no)
All work carried out should be in accordance with all relevant good pratices and or current building stand-
ards. All current regulations should be followed in relation to working at heights. Nothing stated in this guide
takes pre- sedence over current standards.
Condition of Roof
What are the centres of roof rafters where solar collector is to be mounted (eg 400mm)?
(mm)
What is the size of roof rafters (eg 6x2”, 7x2”, 8x2”)?
(inch)
Are roof rafters cross braced?
(yes/no)
Is any of the timber showing discolouration (indicating rot)?
(yes/no)
To determine the total load on the roof you must get the total weight of the collectors and divide this weight
by the number of roof fixing bolts or anchors used to hold the collector on the roof. This will give you the
weight of the solar panels on each point of the roof. You must then carefully review the points where the col-
lectors are connected to the roof to ensure that these exact points can take the anticipated load.
Where there is signs of discolouration a closer examination will be requried. If black spots are found on the
timber this indicates a leak which needs attention. If the timber appears brown and flaky then the timber
may need to be replaced. If the situation is unclear a structural engineers report should be obtained prior to
completing any further work.
Effects of Snow Loads
What is the estimated annual snow fall for this part of the country?
(mm)
The estimated snow load for all parts of ireland may be found from historical data located on Met Eireann’s
website. www.met.ie
What is the total extra weight to be assumed from a snow fall?
(kg)
Irish snow weighs approx 150kg per m3. To determine the extra weight the snow will add to the solar panels
you may assume the following formula.
(snow fall in meters x area of panel on the roof in m
2
x 150kg/m3)
When you find out the total extra weight of the snow add it to the total weight of the collector on the roof.
The using this new weight examine the roof structure to ensure its suitability. You do not need to consider
the snow load when installing evacuated tubes.
Effects of Wind Load
The evacuated tube collector is exempt from consideration of wind loading for the same reason as the snow loading.
When considering flat panels wind tests have been conducted that ensure that they and their fixing brackets can withstand all
recorded wind forces in Ireland when mounted on a four storey house or less.
Risk Assesment
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