A popular question we get asked often in our customer services department is how to work out the right size of extension ladder.
Identifying the correct size of extension ladder is a relatively straight forward task. Putting that aside, however, it is still imperative that the right size of extension ladder is used in order to avoid ladder trips, slips and falls.
Finding the right size in simple terms
If you need a rough guesstimate then you can simply drop a tape measure out of your window. Some people simply measure the ceilings in their home and add another 50-100cm to allow for the ladder pitch and depth of ceiling.
Here at BPS Access Solutions, we highly recommend that you measure correctly to ensure that the extension ladder you purchase is suitable for the job and most importantly of all will not cause a serious injury or worse by incorrect usage.
How to measure for a standard 2 floor house
To measure the length of extension ladder required on a 2 floor house, you can use a very simple formula.
Do you remember the Pythagoras Theorem from your school days? The formula to use is very similar although thankfully it won’t require you to re-learn all the terminology!
Imagine that (a) is your house wall and (b) is the ground on which the ladder will be sitting. The pitch of the extension ladder will make up (c.) If the pitch is too long the ladder will be sitting at a dangerous angle and if too short your ladder will not be long enough to reach the job.
Thankfully our extension ladders here at BPS come in 3 sections, so you only need to use the sections that are needed which allow for greater versatility of jobs. We do suggest ensuring you can reach the top of your house though with your extension ladders.
Getting the pitch of the extension ladder right
The average 2 floor house will be just over 6 metres in height. This means that the base of the ladder must be placed just over 1.5 metres away from the base of the house wall. The top of the ladder must extend beyond the roof edge by approximately 90cm.
If the ladder pitch is not correct, there is a serious risk of the ladder slipping or tipping away from the wall when in use.
Our ladders are amongst the safest on the market today and we promote safe use of ladders to ensure your safety when in use.
How to calculate what size extension ladder you will need
The Health and Safety Executive (HSE) states that ladders need to be at an angle of 75 degrees away from the wall. This is known as the 1 in 4 rule. To get the angle right, you will need to know how far off the ground your roof is.
So assuming our measurements for the 2 floor house – 6 M in height with a Base of 1.5M we then need to use the Pythagoras Theorem to work out the ladder length. You need to square (a) and (b) to get (c.)
- So 6 x 6 + (1.5 x 1.5) [a + b]
- 6 x 6 = 36 1.5 x 1.5 = 2.25
- 36 + 2.25 = 38.25 [c]
- Square root of 38.25 is 6.20 approximately. Add approximately 1 more metre (for ease) to account for additional extension beyond the roof edge, which means you would need a ladder of just over 7m in height.
Things to look out for
Common mistakes that are made with extension ladder length include
- Forgetting to account for dips in the ground
The Pythagoras Theorem calculation assumes flat ground. In reality the ground has dips and bumps in it. Always ensure your ladder will still be long enough. It is better to have a longer ladder than to scrimp on the length. If there are any doubts, you could use a spirit level to determine the difference in ground levels or better still use a ladder leveller which will ensure your ladder is level on the ground.
- Beware of two section extension ladders
Bare in mind that the higher up an extension ladder you go, the more wobbly it gets. This is why at BPS Access Solutions we eliminate ‘the wobble’ by having a three section extension ladder. Not only does this enable you to complete jobs at a lower level, it is also easier to store due to the compact size it folds down to.
- Check the weight rating of the ladder
For maximum comfort and safety, always ensure the ladder is suitable for your weight before purchase. Our ladders have a massive weight rating of 150kg, however they are still lightweight and easy to put up and down.
Remember a ladder from BPS Access Solutions will last for many years to come. Make sure the extension ladder will fully suit your needs before purchase.
