Refer to old articles of aluminium roofing sheets, they come in rolls of average of 600mm to 1300mm depends on the manufacture and specifications. As stated in previous articles, the aluminium sheets comes in rolls at the factory just like toilet rolls but with different widths and thickness based on specifications.

Calculating the roof required could be done by calculating the surface area in square meters of the area covered by the aluminium and for some companies it could be calculated in meter lengths ,knowing the width which is 600mm above as constant.

For a simple gable roof as shown in pic 1 with length of 25.2m. First you must know the height of roof from the section.

For this sample we are taken the eight to be 3meters (10 feet)to know the length of leaf “x” or “y”

Remember the pythagoras theorem

x^{2}=3^{2 +}6.1^{2}

x=6.8m

Hence the area of roof is (6.8 i.e x)+6.8 i.e y) multiply by length 25.2m=342.72m^{2}

If the width of the roof comes in 600mm or 0.6m, the length of the roof require will be 342.72/0.6m

=571.2 meters length

So for some companies they could give their quotations in meter length so just ask for the width of the rols and follow steps above.

For a complex roof like pic 3 above, then you can opt to do a fast estimate based on the linear area covered as shown by roof plan as it may be a bit complex and difficult, so you can divide the roof plan to sections of rectangles or squares as it may applies –(four right angles). Then add the areas together and add 10% of the same area, because the higher the roof, the more the plates , and the more complex the roof the higher the numbers of offcuts which will also increase the numbers of aluminium /plates required . So for pic 3 ,add areas of rectangles A,B,C and D which is the big center.

i.e (8.2m x 1.2m)+(1.2mx8.2m)+(1.2mx8.2m)+(22.8mx12.2m)=311.28m^{2 }

Add 10%=311.28+31.128=342m^{2}

Now for a more accurate and scientific calculation, you must know the height of the roof , have the basic knowledge of calculating area of a triangle which is ½ base x height . And Pythagoras theorem to know the side of any triangle . Also remember the area for a rectangle is simply length multiplied by breadth.

Assuming the height of roof is 3meters as as previous in fig. 2, and taken the major part D as a simple gable roof (check the different sections on plan fig 3) and ignoring the hipped or bevelled section.

x^{2}=3^{2 +}6.1^{2}

x=6.8m

So area of roof as previous is ( 6.8m+6.8m) multiply by length 22.8m=310m^{2}

Add areas A,B,C

+310m^{2 } +9.84m^{2 }+13.44m^{2 }+ 9.84m^{2}

=343.12m^{2}

With your estimate is also the RIDGE and GUTTERS.

Ridge is the roof material you use that will cover and seal up the points where two leaves of your aluminium sheets meet to protect the interior from rain, it usually overlaps the two adjacent leaves of roofing sheets .

And gutter is usually underneath, it gathers rainfall and help to channel it to wherever deem fits according to design. Is at the taper ends of two adjacent leaves of aluminium sheets to collect water.

The difference between gutter and ridge . While the ridge is up protecting rain water the gutter is down collecting rain water and channeling to some drains.

It is very useful guide and educative.

Thanks

Thanks. It has been helpful.

This and other articles by Arc. Omion have been very helpful. Omion is one of the rare experts in his field who has single out himself to practice his profession not for the sake of money, but to be a solution to humanity.

I love this, ride on Omion

It is refreshing and educative. Please keep it up.

Thanks.

Ur description is too technical always. Kindly find ways of simplifying wwhat you’re saying. I’m personally still in the dark.

All the articles on this site are written bearing in mind that they would be read by a layman, infact they are not meant for the professionals so the articles are extremely simplified already but I will try more.

Nice job, this is a refresher course thanks.

Good reminder to our ‘O’ level mathematics.Highly informative and educative. To a great extent, this will reduce some of the sharp practices by fraudsters.

Keep up the good job.

Hello, thanks for all your efforts in making construction actually very interesting in one way or the other. Pls kindly email all the registered Building/Civil Engineering firm/company in Lagos state that you have their records including their email addresses, location, website if they have. Thanks, God bless you. I

Well Sir, dt was very easy and straight forward. I must admit dt most of ur articles I av read and are extremely helpful.

But calculation a long span is yet more complex and yet easy, but not as u’ve outlined. If u do, u will either be wasting material or end up not avin enuff.

Some factors are so necessary before the calculation. Like the thickness, the slope, the width and the numbers of gutters.

Well I knw ds cos av worked with an indigenous roof manufacturing and installation copoarte company, and a building technologist. Though jobless now.

But all the same Sir, I’m alwys blessed by ur articles.

Thanks for droping this at our doorstep.

Thanks for educating the people in order to guide them in their project execution. God will enlarge your own coast

Good work. package this in seminar for people to take an advantage of practical art of it at affordable rate.

Thanks

GOD BLESS U

thanks for your asistance

We could design roll forming machines according to customized profile if you need anything ,plz feel free to let us know ,tks

Infact i can build now

Infact i can build now

Now please i still do not understand. I want u to help me to calculate how mush will it couses me to Roof 4bed room flat apartment, and 2flat apartment 3bedroom each in a flat bout roofing sheet and wood. thanks

Good we are grateful with your post keep it up thanks. But sir i wish to know sizes of roofing sheets

Infact this is aided and encouragious

thanks

This is an incredible roofing estimate diagram you have designed her regarding aluminum roofing shingles. you really go into detail her with your expertise. i just learned some new things by reading this entry. The calculation that you have put together here come from a true roofing expert in the industry. Very solid material.

Roofing sheets is a good technology…thanks for posting in your blog…keep on posting about Roofing Sheets….

I will like to knw if it is wise t buy d aluminiom sheet frm Tower lagos, bcos I learnt dat its cheaper dan in ilorin. Thank u

Tnx alot 4 dis ‘internet classroom’,nd i wish 2 knw of wat length s a roofing sheet projecting beyond faecia board(concrete nd wooden).

You have really help alot of us here. Thank you very much.

tnks,kip it up,it realy help me

I just want to say You are a great man. The information is worth more than a million my brother. Just know that only a flowing river is contantly refreshed. information sharing is key.

Weldone sir I appreciate all your effort but I still don’t understand the measurement presently I have 4 bedroom flat around odokekere and I’m about to roof it.the expert told me after carpentary work that I ll need a total 565m of aluminium roofing sheet or 15 bundles of pan depending on available cash plz how many sheet of aluminium roof sheet will I require base on that meters above. Please help me out.

Great work! Keep up

gud job keep it up it is very amassing, interesting, and educative more freeze to your elbow.

my house measures 26mX11m, with 4m kingpost my engr quoted 790k for aluminium roof,including labour. is it a good deal. thanks

You are a blessing to this generation.

I really appreciate the knowlege shared by the initiator of this topic, it has been helpful really. Buy some things are not clear to me. After getting the overall enght required, how do we know the lenght to cut each plate into from d factory, since each plate has different lenght on the roof, especially in complex pitched roof with d highest plate at the apex. Thanks

Gud day sir, i understand ur explanation but ur digrams/sketches is not clear to me, if possible help send me the attatchment of the diagrams, thanks.

Just doubleclick on the diagram it will be emboldened.