Renovation, extension and particularly challenging driveway conundrum

[Saucisson]

Hi - good to be here, thanks. My partner and I stumbled across buildhub whilst googling "huge retaining wall driveway". It led us to a few posts with helpful responses, so buildhub seemed like a great place for us to get some help. We've just moved into a 1930's semi-detached house that needs quite a lot of work. It's our first house and in comparison to other projects here, I'm sure it seems quite mundane. The one thing that we really need help with, that may present a relatively interesting challenge to someone, is our desire to have a driveway. We are getting mixed responses from people who know more than we do as to whether its actually possible - our architect was a bit stumped, advised that we needed a structural engineer but he would think about some potential designs and come back to us. We were hoping someone else may be able to provide any info/experience of similar problems. We have a lot more work planned but it made sense to do the driveway first to make it easier to get materials to the house at a later date.

 

I've attached a couple of pictures to help anyone who wants to understand the problem. I have listed some more information that may be helpful below. Photo 1 is taken from the road outside the house. Photo 2 is taken from the window above the front door to give another angle. Photo 3 is taken from the garden which shows the space to the side of the house. Photo 4 is a potential solution:

- The house is at the bottom of a what you could maybe call a culdesac. It used to be a road but then bollards were put in, meaning our house is now at the end of a dead end.

- The road slopes downhill, there are houses to the left of the photo and houses opposite.

- We want the driveway because one side of the road (the opposite side) is used for parking which is mostly full. You can only get one car up and down at a time so the houses on our side have issues parking. They either have a driveway of some sort (ranging from a slope up to the side of the house, to a circa 2m concrete indentation within the "earth" outside the front of their house which fits half a car, the other half is on the pavement). Alternatively they find off street parking nearby. We only have 1 car but people use the area outside our house to turn their cars around. The previous owner parked on the pavement but if we have friends round / parking on the curb becomes an issue further down the line - we'd rather not deal with the faff.

- The picture probably doesn't quite show how high the house is. Its roughly 8.4m from the fence on the right hand side of the house to the back of the pavement. Its roughly 3.4m down from the front door to the bottom of the steps in height. 

- In case it is unclear, there is a garage behind the parked car - we own this garage. It is falling down and not structurally sound. We were planning on knocking this down.

-We own all the land to the right of the house, up until the treeline you can see. On the other side of the tree's are railway lines which according to the research we have done and our architect are far enough away to not be an issue. The railway line is to the right of the fence on Photo 3.

 

What we are looking to achieve:

- Our initial plans were to have a driveway running from where the garage is now (there's a dipped curb in-front of it) along the side of the house that runs far enough for the drive to be at a steepness that is practical. We've been told this wouldn't be a good idea as the driveway may end up running quite close to the foundations of the house.

- If the above is indeed impossible then we would consider something similar to the third picture attached. Although I understand we are a lot higher!

 

Any help would be greatly appreciated. Hopefully someone finds this an interesting problem to fix. Any solutions we hadn't thought of or ideas of costs would be greatly appreciated.

p.s. sorry some of the photos are in the dark. I've only just thought to take them now whilst writing the post out.

 

Thanks

Saucisson

 

 

 

[ProDave]

You need professional input to avoid you doing anything that resultsin the house sliding down into a big hole.

 

Can you not repair the garage and use that, it will be by far your simplest form of off road parking.  If it has been built properly it will have been built into the hillside with retaining walls.

 

What is to the right of your garage?  is it right on the boundary or is there scope to widen it by rebuilding the retaining wall further to the right?

[TonyT]

Agree with ProDave, be careful. I excavated approx 140 tonnes to create my driveway and had to hold up the corner of my house and garden with a 2.5 metre high wall, luckily old school builder and SE did a great job

[Saucisson]

54 minutes ago, ProDave said:

You need professional input to avoid you doing anything that resultsin the house sliding down into a big hole.

 

Can you not repair the garage and use that, it will be by far your simplest form of off road parking.  If it has been built properly it will have been built into the hillside with retaining walls.

 

What is to the right of your garage?  is it right on the boundary or is there scope to widen it by rebuilding the retaining wall further to the right?

 

@ProDave please find the answer to your question re right hand side of garage attached. 

Not a single person we know has suggested widening the garage. I'd written the garage off due to it being too small and not structurally sound. We should probably re-consider who we associate with! Thank you @ProDave - I'm already glad I posted. Our preference is still to have a driveway but you and @TonyT make good points re the risks of the house sliding... not a pretty thought! If we had a wider garage it could solve the problem. Along this line of thinking - would it be possible to widen both ways and put in new retaining walls? I'm not sure at all what was meant by the garage not being structurally sound when we were told and whether there are retaining walls that are fit for purpose around it. It's something I now know to look in to.

@TonyT - do you know how many tonnes we would be moving/how it compares to what you did? I'm guessing our wall would need to be higher than 2.5m if we went down that route.

[TonyT]

http://www.civil-engineering-calculators.com/Quantity-Estimator/Excavation-Calculator
 

 

Afraid I just left the guys to it, thankfully the guys doing the excavation also own the village dump /skip company so excavation costs were minimal.

 

soil does bulk up when excavated approx 30/40%. So take this into account.

 

 

[Saucisson]

5 minutes ago, TonyT said:

http://www.civil-engineering-calculators.com/Quantity-Estimator/Excavation-Calculator
 

 

Afraid I just left the guys to it, thankfully the guys doing the excavation also own the village dump /skip company so excavation costs were minimal.

 

soil does bulk up when excavated approx 30/40%. So take this into account.

 

 

 

much appreciated