There are two ways to create a ground plane in SketchUp.

The first is using the line tool, rectangle, etc. and the measurements taken from your site analysis.

The other is to import an image such as a scanned copy of your base plan.

Do this by using the Import Image tool and then click it to the origin.

Stretch it out. It doesn't have to be to any particular scale at this point, because we're going to use the tape measure tool to set the scale.

So with that tool selected, we're going to click on two known points.

And we need to know the distance between those. So in this case, we're using the top left corner of the house.

Coming down to the bottom left corner and we know that measurement is 8.6 metres.

So once we click the second time we'll then type in the dimension 8-6-0-0 and Enter.

And then say Yes to resize it. Now we can use the zoom extent tool to show us the whole working model.

And we're gonna group our face plane drawing.

And we are also going to create a tag for it and assign that tag to this object.

That'll make it easy for us to hide and unhide it as we need to.

Next we're going to start drawing our surfaces.

So in this case it's draw a rectangle.

We know that the building is 8600 by 3050.

So type it in. And now we've got a shape that represents the building.

Okay to turn this into a group so that it doesn't stick to other geometry.

We're also going to create a new tag. And at some point you will assign this object to that tag.

Now we are changing over to x-ray view so that we can see the drawings underneath.

We are doing it 200 millimetre offset to add the walls and then making a few changes to represent the front of the building,

which has the small veranda included.

We use the tape measure tool to create guides, at all the points we need to add openings for windows and doors.

And we have some of those dimensions available from our site survey. 

Im using the rectangle tool to create those shapes.

Snapping to the midpoints where possible. You can see that the drawing we're doing doesn't entirely line up with the drawing from our base plan.

If accuracy is particularly important, then it would make sense to do this base plan from your measurements.

But because we're working simply on the concept stage, it's right that it's, a little less accurate.

If you're at all concerned about the accuracy, please do use the measurements from your site analysis to draw it up from scratch. 

This house is actually a couple of degrees out of alignment of the main house with Genevieve's house.

So we're being really particular here to get it to the right point.

This won't line up with the red and green axes instead here get parallel and perpendicular alignment guides.

We are using that down arrow once or twice.

It doesn't work in all cases. So now we're going to use some guides. 

If you do find when you're creating guides that you click and it doesn't pull off separate guide — it starts measuring from point to point?

It probably means you've clicked on an endpoint or a midpoint.

So just click Escape to undo that and try again.

Now we're going around using the guides to outline the shape, using the line tool.

What you'll notice is that we're zooming in quite closely to these points, because by default,

SketchUp will snap on to the red and green axes, and in this case the building is somewhere around four degrees out.

So unless you zoomed right in close and you can see those intersection marks, it's probably not.

You can see right here snap to the axis state.

So pay particular attention when you're closing shapes that you do fill in.

If when you get around to the end it doesn't seem to fill in the shape with the surface,

then chances are that you haven't completed all the faces that add up to to the shape. 
Let's see here. We've got a problem with the geometry. We've created a small line along the axis instead of joining up to the intersections.

And again we still have an issue. We can check this because when we click on one shape the two are

being highlighted with blue dots. Now we've got it's three separate paths. 

Now we're gonna import the concept plan.

And luckily, we've scanned this,

set it up on the same page, and scanned it in the same orientation, so we can import it as we did for the base plan.

But this time we're going to drag it out and snap it to the edge of the other.

Joy. Looks like we haven't grabbed the origin point correctly, so we'll try it again. [silence]

Got hooked onto the origin, snapped on to the other edge, and that should be right in place.

Going to make it into a group and assign a tag to it. [silence]

So we don't need our base plan anymore. Now we're going to set about drawing guides and based on what we've got on our concept sketch.

Sometimes we'll use that drawing. Remember, this is just the concept, so it won't be particularly accurate.

But at other times we might know the dimensions we want, in this case 4200 millimetres.

Likewise, here snapping two elements of the building. [silence]

As you can see here, we're drawing, our guidelines off the relevant building 

so the landscape nearest the mansion house is going to be, rectilinear to that house,

whereas the area near the catio and the entrance to the Marten house is closer to the main house on the side on that sort of four degree offset.

Now we can use the line tool to start forming the shapes, drawing in the hedge.

And the existing Garden bed. [silence] And because we've set up the guidelines, we can snap to those intersections. [silence]

Checking here to see that that is one shape - the lawn space and it is. [silence]

We're gonna use the face offset tool to select the face and offset it by 100mm.

This is one of our raised garden beds and I repeat this process on the other four.

So once we've typed in 100, select it, select the face offset tool and double click it to apply the same dimension as last time. [silence]

Right. Clear all the guides that are in this group.

Clear the guides outside the group as well. Double click back into the group and carry on editing.[silence]

Using the down arrow to constrain to the parallel perpendicular axis there. [silence]

And because that design is going to use rectilinear pattern in the garden beds, we're going to actually snap to these offsets

and then drawing the lines, which we may come back to and add more detail in later. [silence]

You're gonna turn off x-ray mode. See how it's going. Okay, now that's the fun part.

Going to use the Paint bucket tool which is the B shortcut key.

And we can fill it in our shapes using some basic colours or textures.

In this case, we're going to bring back the X-ray mode so we can see what's going on actually realising that

there's a bit more modelling to do. We want to extend this deck into a series of stepping stone boardwalk pavers.

So we're going to use the guide tool here.

And we know that those two are 400 apart and they're offset by 200.

So we can move it 600. And then duplicate.

That gives us quick guides for spacing.

You can use the rectangle tool to fill in the shapes. [silence] Finally, when we want to add in some pavers, a 400 by 400mms.

And we are now Exited the group and we creating this 400 by 400 rectangle on top of the group.

And the reason for that is we want to be able to move copies of it,

space them out just right. Now we're going to select.

all of these shapes. Use the Cut command.

Control X. And go Edit the group.

So double click into the group and then Paste-in-Place — that will place those shapes inside the group.

You can see they're now they're part of the geometry of the group.

And now we're going to get into applying some colours and textures to make the design look how we intended to look.

So using this light green grass colour for the grass areas.

Different colour for the low planting in the ones in raised planter boxes.

raised beds, dark one for the hedge, and then some mid greens for the lower planting areas.

It's entirely up to you what colours you choose, but make ones - 

choose ones that make sense for you. [silence] We're filling in our deck, and our raised planters using a wooden colour. [silence]

And we're done.