Builders, help! What should I do with sloping block?

Any advice would be greatly appreciated.

I'm building a duplex on a site which slopes approximately 1 metre from the rear to the front (rear is higher) and have to decide whether to:
A) Build the home above the natural ground level at the rear and have steps entering the house at the front, steps from garage into internal spaces, and elevated driveway, and anything else I can't think of ATM; or
B) Build the home above the natural ground level at the front and have retaining walls along the boundary, cut the higher ground at the rear, and anything else I can't think of ATM.

I know if I went with option B, it'd look better from the front but retaining walls would somewhat ruin the rear yard, and if I went with option A, the front yard would be ruined.

What are your thoughts?
 
If I went with option B, I'd have to get rid of a large tree in the rear yard so I can push the retaining wall close to the boundary. There's also a large gumtree in the neighbours yard approximately 2 metres from the boundary, hopefully it's roots aren't in the way.
 
Would be cheaper and easier to fee rid of the trees when the block is cleared. Unless they are nice looking or you want to keep them. They could be s liability in the years to gone.

2m to you're neighbours tree is close. The rule with trees is that the roots go our as far as the branches above
 
also consider using steps in the house as a split level plan feature. i personnally think that a stepdown living area looks very good...
 
1m isn't much so you have lots of options.

I would talk to your builder and see what is most economical and I suspect it will be
1. raise front block 300mm at front (around one limestone block) for the garden area and slope the driveway gently up to the garage. Fill from rear block.
2. retain front of second block at front (or rear of front) by 300mm and have house one level with continuation of gentle slope for driveway.
3. retail 300mm at rear of second block and put rear fence on top

Cutting 300mm from rear block and putting that into front block should even out the sand levels about right and there shouldn't be excess soil.

300mm is easy to retain height and needs less 'engineering', less drainage problems and no council permission in my state. It can be construction from limestone blocks, blocks, and concrete panels.
 
I visited the architect and stormwater engineer this morning regarding the issue and we came to a solution. So just to recap, the rear of the block falls from the rear to the front and I'm building an attached duplex side by side. What we agreed on which I think works well is to build a retaining wall on the rear edge of the alfresco and have a few steps leading to the rear garden, that way I can still make full use of the rear yard without having retaining walls cutting through the yard. What they had initially proposed was to build a retaining wall parallel to the alfresco but 1-1.5m behind it, which would've reduced the size of the yard.

Whilst we're on the topic of stormwater, what ya'll think about osd's under the garage rather than the driveway?
 
^ By this, do you mean that the rear yard level will be higher than the floor of the alfresco area, and so when sitting outside in the alfresco area, you'd basically be looking right at the retaining wall...?
 
Yes, exactly, but the retaining wall be at most 500mm high and will taper off through the length of the alfresco. The alfresco is 9000mm wide and 3600mm long and the retaining will only span half the length.
I'd rather have a retaining wall by the alfresco area than a retaining wall cutting through the rear yard and halving the effective area.

See the attached image. The height of the retaining wall will be say 31.000 and the FFL of the alfresco will be 30.600. The retaining wall will run along the boundary beside the house then kick along the rear of the alfresco.
The tree in my property can be removed (I'd rather keep it) but the one in the neighbours could be problematic due to its roots.
 

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Got a photo to go with the drawing?

Id agree that you dont want a wall in the middle of the yard. but I wouldnt really want one at the alfresco area either. Can you just wear the slope, or at most try and keep it to <250mm ish or what the standard is for a single step. Treated pine sleeper is 200mm and lose the rest of the slope across the yard?

Id think osd in the driveway wouldnt want that under the gargae
 
My advice for sloping lots remains the same.

Put the money into the house instead of the lot. So many people (especially in Perth) level the lot off them build a 'standard' home, spending $50k on the lot levelling to save $25k on the house construction to have a dwelling that has average appeal and average value. You might as well have dug a Dale Kerrigan and dropped a bag of $100s into it.

If you put the money into the house, you can have a very original, correctly zoned home that cost a bit more but has a much larger intrinsic value and a wider market appeal.
 
Aaron, what you're saying worked fine when houses were built on piers, all you needed to do was slap on some steps on at the front or rear door and you wouldn't have any stormwater issues.
Now that majority of homes are built on concrete slabs, it's a little more difficult to manage stormwater, hence why many are cutting and filling.
The issue I'm having is due to stormwater runoff, not aesthetics. I'm only trying to come to a reasonable solution whilst maintaining a decent rear yard.
 
no issues with stormwater with this one.....

concrete slab construction et al and 2m corner to corner.

these sold quickly and for more than expected during a low period in Perth because they were different.

maybe that's the issue - not thinking laterally.
 

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I visited the architect and stormwater engineer this morning regarding the issue and we came to a solution. So just to recap, the rear of the block falls from the rear to the front and I'm building an attached duplex side by side. What we agreed on which I think works well is to build a retaining wall on the rear edge of the alfresco and have a few steps leading to the rear garden, that way I can still make full use of the rear yard without having retaining walls cutting through the yard. What they had initially proposed was to build a retaining wall parallel to the alfresco but 1-1.5m behind it, which would've reduced the size of the yard.

Whilst we're on the topic of stormwater, what ya'll think about osd's under the garage rather than the driveway?

Ah you didn't mention they would be side by side. That does change a lot.

I have a client with a greater slope but still upwards and he will be having 4 steps inside the house and then a small 300-600mm retain via a box planter on the rear of the alfresco

Just remember that to mow the rear garden there needs to be a way to get the lawnmower up to that section. Some sloped area towards the side can help with this
 
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