Tips for Basic Roof and Slope drawings

Hello Professionals, basic Sketchup user here

I started using SketchUp for private use as we were remodeling our apartment. It was super and helped us alot!

I work in the roofing business, supplier of materials, and oftentimes our customers ask us for help with calcualiting and offering tapered roof systems (using sloped boards to create a slope on the roof).
Today I work in Adobe Acrobate PRO using their measure feature, and drawing my own lines to help keep track.

But yesterday I recreated the roof plan in SketchUp and used the correct slope degrees to make a model of the resulting tapered roof.
This however took a lot of time and was quite tedious.
But our customer the roofer was happy with the model and the building owner really liked these drawings.
We are a small independent company of two people, and do not have the need nor knowledge of getting the complicated systems such as AutoCAD for example, that our very much bigger competitors use.

But I have two questions that might make things easier for me in SketchUp.

  1. Usually we receive the drawing in PDF format, where I input the corerct scale in Adobe PRO and start measuring.It takes a lot of time and the end result is not so nice.
    Is there a way to put this drawing in SketchUp and giving it correct scale from the beginning?
    So I could outline the roof and get correct dimensions directly.

  2. Is there a way to create “personalized” grids?
    When calculating the number of “sloped boards” needed, i just put in the dimensions of the boards using the Tape Measure tool. So the baords are 600mm wide and 1200mm long. If the roof is 12x12 meters - i need to use the tape measure 20 times on the width and 10 times on the lenght.
    But could you create some kind of grid with box dimension of 0,6x1,2m that keeps it’s dimensions how ever long you drag it? So i could just lay the grid over the roof?

Example of my output and the origianl drawing. I have drawn all individual lines using tape measure. Quite time consuming as you could imagine.

I realize these functions might be already included in programms such as AutoCad or similair. But we are not architects or designers, this is the only use we would have so we don’t really want to put in the money for these systems we wouldn’t use.
So thankfull for any tips or tricks you might have!
/ Odlmag

You seem to be using the Tape tool to create construction lines, which is fine. However, if you want to place such lines at regular intervals (600mm or 1200mm, say) you would just move/copy the first one by the relevant distance and then type x20 (or whatever you think it will divide up into - doesn’t matter if it’s too much for this purpose). You can do the same thing with an actual line.

If I were doing this exercise I would probably start with an end profile, suitably tapered and divided up. Then use Push/Pull to stretch it to a bay width. I might then make the 3D element created into a Group and copy it however many times I needed. Finally, to create the mitre cuts on plan I would create a temporary cutting “box” and use Solid Tools to trim individual groups.

It sounds to me like you are not using Sketchup in the most efficient way.

Problably I am not :slight_smile:
Learning by doing, since designing my kitchen and living room last year.
So this purpose is all new to me, but might save a couple of hours every week!

Very interesting about placing lines at intervals!
Although I am not sure how you do it as explained?
I tried, but when moving a line over a surface with the move copy (crtl move) function it says “Invalid Length” when I type x20.
I can move it once at 0,6 meters by just typing “0,6”, but when do I type “x20”

You must complete the move of the first copy by hitting enter after the distance, and then after that you can type the number of copies to create.

By the way, when rotating an object up, or creating guide lines with the protractor tool, you don’t have to enter degrees only, you can enter the slope. For example, you can type 4:12 in the VCB for a 4" in 12" roof pitch instead of what ever that works out to be in degrees. That way SU does the math and you think in your usual terms.


The one we use in our part of the world very often is 4:3, creating a hypotenusa of 5…

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Convert your pdf plan to a jpeg or png and import as an image. Make sure your model space is in the same units as your drawing (metric, imperial) and then with the tape measure tool, snap along two points of a known length on the plan, then just type that unit in (do not need to click inside the measurement box, just type) you will get a note asking if you want to resize the model ans click yes. If you then draw your geometry on top of this it will be at the right scale.
You can also draw from the beginning and do the scale afterwards too, but by doing it first you then have the option to enter know lengths as you draw.

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When tracing lines or assigning scale to an imported image, it is important to be careful where you click, as the lines in the image are not SketchUp geometry and won’t provide horizontal snaps, only “on image” snaps. Because many drawings, such as the one in the animation above, have variable line thickness, it is fundamentally ambiguous exactly where the measurements extend to. The inside of the line? The center of the line? The outside of the line? This uncertainty and need for exactly choosing your click points means that the dimensions may be slightly wrong.

On a different note, it appears in the animation that the rescaled drawing ends up quite a distance from the model origin. You should move it close to the origin, as SketchUp doesn’t do well when geometry is far from the origin.

And here’s another way to do it.

Nice, and I’d add that by making the initial slices into a group you can more easily delete the scrap in one fail swoop.

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Another approach. I didn’t do that last bit, which I could do the way you did, but using the Rotate tool sped the rest up a bit.

You’ll end up with faces that aren’t vertical but slightly off!

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Good point. Here’s yet another way, that doesn’t have that problem.


If you are just after the “grid” perhaps try this:
Using Sandbox tool “From Scratch”…select the tool and enter 1200mm in the measurements window. Drag out to create the grid in a size large enough for your total roof area. This will create a grid 1200mm x 1200mm.
Now move/copy the whole grid you have just drawn over to the halfway point of a single square in the grid to create the rectangular grid you are after. 1200mm x 600mm

If just determining the number of panels you will need you should just view from above using parallel projection top view with the grid placed above the roof and in wireframe mode or paint the grid with a transparent material.
Sounds more difficult than it actually is…sorry I don’t do the snazzy .gif animations.

If you wish to label or number the panels you may find this extension useful. Numbering Text by Didier Bur

Numbered w/Extension

Roof_Grid_V8.skp (471.3 KB)

Hey Guys,

Thanks for all of your input, I will put it to the test today!

Can already see this saving me a lot of time.

Amazing what can be done with this free(!) program.
I almost feel sorry for our bigger competitors paying tens of thousands of dollars for plug-ins for their licenes :slight_smile:

Really Appreciated!

It sounds as if you are using the program for commercial use. You cannot use free versions if so and must have Sketchup Pro.

Since what you do with it is clearly workrelated you should be using the pro version…
Make is only for non-commercial purposes.

Sketchup Pro costs just a fraction of that so you can still feel sorry for them…

@simoncbevans @tweenulzeven

Ok, did not know! Downloaded it for personal use a couple of years ago - am on the 2015/2016 version.
Just thought there was a difference in functionality - but will of course do our dues if this turns out be a benefit for us!

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The “grid” of multiple (self copying) tiles attached is dynamic, you can use it via the dynamic components tool bar.
Currently it works on user input rows , whereas the length can be input or scaled for number of units in a row
There are two angle inputs to save the need for deleting the ends.
You can change the slope and starting height
The interact finger reports the range per tile
If you do go ahead with the Pro version then you could alter the component workings, add attributes to generate a report, quantity list and display the results in layout.
Hopefully this will sway you in your decision
you can get the Sketchup Pro trail for 30 days, use the forum to set up the workflow, then maybe subscribe or get the perpetual version.

slope tile.skp (310.3 KB)

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Very nicely done!