Sensible size and gradient for a garage door entrance ramp.

[epsilonGreedy]

I am starting to think ahead to the FFL of my garage which will be a ground baring concrete slab. The garage is separate to the house and the adjacent gravel driveway is flat with a very slight gradient away from the garage door.

 

Are there any industry metrics for a maximum height difference between external drive and garage floor? Other local factors favour a higher garage floor but a don't want a clutch burning sharp ramp incline when entering the garage. I am unlikely to be concerned about the front ground spoiler of my Ferrari (joke) grounding out on the ramp. The garage is not deep (5.3m) so I want to avoid creating a daily parking challenge that would involve revving the rear wheels up the ramp and then hitting the breaks to avoid nosing into the rear wall.

Edited January 17, 2019 by epsilonGreedy

[Weebles]

I have a related question so will, for the moment, keep it on this thread.  What does the "join" between driveway and garage floor look like?  Any photos out there to help explain it?

I am planning a garage door behind the piers of the garage so there will be a bit of "floor" sticking outside the door (or a bit of driveway running into the revealed area?).

It seems to make sense to join at the rear of the reveals.  But I want to make sure that no water can get through my driveway onto the concrete slab that is then under the rest of the garage.

We can create a slight incline to make sure that water runs away......

Any advice please?

[ProDave]

The gradient is not the issue, it's the rate of change.  I see lots of people have a very short very steep ramp which could be either the clutch burner, or spoiler catcher.

 

Why not just grade the aproach so you make any necessary rise over the length of a car?

 

We have the opposite problem, the garage is lower than the road so we have a slope down to the garage, then a very small step up (with a drainage channel) to prevent heavy rain filling the garage.

[Oz07]

51 minutes ago, Weebles said:

I have a related question so will, for the moment, keep it on this thread.  What does the "join" between driveway and garage floor look like?  Any photos out there to help explain it?

I am planning a garage door behind the piers of the garage so there will be a bit of "floor" sticking outside the door (or a bit of driveway running into the revealed area?).

It seems to make sense to join at the rear of the reveals.  But I want to make sure that no water can get through my driveway onto the concrete slab that is then under the rest of the garage.

We can create a slight incline to make sure that water runs away......

Any advice please?

I've just set one up using edging blocks tipped outwards and I'm going to have a trowled chamber and arris where this joins. Concrete will protrude out around 20mm past door but not to concerned about small amount of rain running onto it. Could paint/tank this strip.

 

Gradient I'm doing an inch or so in around 1200mm with paving set half inch below kerb blocks 

[epsilonGreedy]

26 minutes ago, Oz07 said:

I've just set one up using edging blocks tipped outwards and I'm going to have a trowled chamber and arris where this joins.

 

 

This is very useful. I was already thinking about using a row of such blocks, will you bring the under slab tanking upwards inside the inner vertical face of the edging blocks?

 

30 minutes ago, Oz07 said:

Concrete will protrude out around 20mm past door but not to concerned about small amount of rain running onto it. Could paint/tank this strip.

 

 

Like you I am not that worried about a small amount of rain landing on the exposed concrete slab, my previous Bryant Homes house experienced the same and that was an integral garage.

 

37 minutes ago, Oz07 said:

Gradient I'm doing an inch or so in around 1200mm with paving set half inch below kerb blocks

 

 

So about 1 in 50.

 

In my case I was considering a formed concrete ramp starting 10mm below the edging blocks then dropping about 50mm over 600mm horizontally.

[mvincentd]

1 hour ago, Weebles said:

a bit of "floor" sticking outside the door (or a bit of driveway running into the revealed area?).

For me this reveal is a 350mm wide area of the garage slab that happens to end up outside due to the fitment of the door being against the inner face of the built opening.....like you’re planning I think.  My door will be a sectional that rolls to ground with a rubber bottom edge that squashes slightly when fully grounded.  that “squash” is designed to be minimal with my particular door (Hormann) and i’m not wholly sure of its rain blocking abilities, especially given a couple mm of variance in the slab over the width of garage door anyway.  Therefore i’m putting a  Rubber weather stop across the threshold onto which the door will close.  These are typically 15mm high so will block water until it’s weight due to depth will send it running in the outward direction where an aco drain will catch it.  Therefore rain travelling in isn’t a concern.  I had considered creating a fall at the reveal but think i’d still use the weather stop anyway as wind could push water up it.  The Hormann fitter says if I use a 15mm weather stop they want to fit the door 15mm higher so it’s degree of “squash” remains as per designed.

My greater concern is with water carried into the garage by wet car, bikes, kayaks etc.

[Oz07]

I could bang a row of oncrete edgings in behind these if other forum users think rain runoff from door splash will be excessively bad? Will tanking/painting first 2" be as good?

 

Yes btw plan is to lap dpm up behind these 

[epsilonGreedy]

1 hour ago, ProDave said:

Why not just grade the approach so you make any necessary rise over the length of a car?

 

 

I am subject to a SUDS motivated planning condition that requires a gravel drive. My working assumption is that I cannot form a large stable ramp to the edge of the garage floor slab from a 50mm size hardcore base with 20mm size hardcore over and gravel dressing on top.

 

1 hour ago, ProDave said:

The gradient is not the issue, it's the rate of change.  I see lots of people have a very short very steep ramp which could be either the clutch burner, or spoiler catcher.

 

 

Ok. Think I need to reduce my expectations about the overall height difference I can implement between gravel drive and concrete FFL.

 

Now looking at: Concrete FFL > Edging stones with say a moulded 20mm drop > 10mm drop to start of external concrete ramp > 50mm gradient in concrete ramp that is 600mm wide > then level to main gravel drive.

 

I already have 150mm of hardcore down for the drive and some flexibility about how much more is layered on top as a finishing exercise when the main build is complete. 

 

 

[epsilonGreedy]

9 minutes ago, Oz07 said:

Yes btw plan is to lap dpm up behind these

 

 

Hmm having suggested this I am now onto Plan-B.

 

My new concern is that these edging blocks might start to wobble following repeated vehicle transits, so would it be preferable to have a concrete/mortar bond on the inner face at the risk of more moisture ingress? These blocks look like engineering blocks.  

[Weebles]

 

30 minutes ago, mvincentd said:

For me this reveal is a 350mm wide area of the garage slab that happens to end up outside due to the fitment of the door being against the inner face of the built opening.....like you’re planning I think.  My door will be a sectional that rolls to ground with a rubber bottom edge that squashes slightly when fully grounded.  that “squash” is designed to be minimal with my particular door (Hormann) and i’m not wholly sure of its rain blocking abilities, especially given a couple mm of variance in the slab over the width of garage door anyway.  Therefore i’m putting a  Rubber weather stop across the threshold onto which the door will close.  These are typically 15mm high so will block water until it’s weight due to depth will send it running in the outward direction where an aco drain will catch it.  Therefore rain travelling in isn’t a concern.  I had considered creating a fall at the reveal but think i’d still use the weather stop anyway as wind could push water up it.  The Hormann fitter says if I use a 15mm weather stop they want to fit the door 15mm higher so it’s degree of “squash” remains as per designed.

 

 

Our reveal is 200mm deep and we have the same plans I think.  We are also looking at a Hormann sectional door so this rubber weather stop sounds like a plan.  Thanks ?

 

31 minutes ago, mvincentd said:

My greater concern is with water carried into the garage by wet car, bikes, kayaks etc.

 

I guess this water just has to be mopped off your floor surface?  We were looking at these floor tile things but not sure they are going to stop water getting through the gaps?  https://duramat.co.uk/product/discplate-black/

We will eventually be using the back of the garage as a games room so definitely want to ensure it has a watertight floor.

[joe90]

We have a roller shutter door with a Rubber seal at the bottom and a 500mm overhanging roof but if it rains and is windy (mostly here) the rain drives under the seal. I wish I had sloped the concrete floor from the door down to the drive a bit. The drive is being tarmaced soon and it will have a slope away from the door. To cure the door problem I am going to cut a floor slot and drop in a piece of flat steel on edge for the rubber seal to sit on/in front of. 

[mvincentd]

On 17/01/2019 at 21:45, Weebles said:

guess this water just has to be mopped off your floor surface?

Yes (will...still under construction).  If I could go back I would have put a drain inside to mop into, laid the slab to a fall and increased that fall at the threshold.

 

22 hours ago, joe90 said:

To cure the door problem I am going to cut a floor slot and drop in a piece of flat steel on edge for the rubber seal to sit on/in front of. 

A friend did this recently, it looks tidy, hasn’t been severely tested by weather yet but I like the idea and may copy if proves necessary.