Waterlogged Garden in Newbuild

Thrugelmir

In the spring dig the garden over. The ground will be compacted. Dig plenty of compost/grit in. We're clay soil and always have puddles on the lawn in periods of heavy rain. The house has been here approaching a 100 years. 

Robby1988

Waterlogged gardens are very common with new build properties.  My father in law has bought two new builds & had to install land drains in the back gardens of both. 

If turf in the back garden is ever a paid extra on a new build, don't bother. Move in & get the pros in to assess the ground conditions and get it prepared properly before laying turf. 

tim_london

If it's a new build - chances are there is a waterproof geo-textile sheet under the layer of topsoil.  Usually this is designed to stop groundwater flooding and contamination (especially if build on old brownfield site) from coming up.   The issue is this layer also stops water being soaked downwards, thus increasing chance of water logging.

I'm not a construction expert, but maybe you can research on feasibility of moving that layer lower?

weeg

tim_london said:

If it's a new build - chances are there is a waterproof geo-textile sheet under the layer of topsoil.  Usually this is designed to stop groundwater flooding and contamination (especially if build on old brownfield site) from coming up.   The issue is this layer also stops water being soaked downwards, thus increasing chance of water logging.

I'm not a construction expert, but maybe you can research on feasibility of moving that layer lower?

Happily, I am something of a mass  house-builder expert. (I'm a engineer for a consultancy and that's 90% of our workload).

Waterproof geotextile membranes are only used as a last resort. It's more common to try and excavate, or remediate the ground if it's contaminated. If there is one under your garden (which is pretty unlikely) moving it would be a bad idea and would be unlikely to have any sort of good outcome.

The thing is, gardens are very much an afterthought to the houses. It's usually just a case of chucking down some subsoil and turf at the end of the build - 100mm or so. Beneath that it varies, depending on what was there to start with, but often there is a well compacted top layer from construction plant etc. Start with making a pattern of holes to see if you get through it to a more permeable layer. Beyond that, field drains are probably the answer.

In Scotland (where I work) it's almost impossible to get permission to put new surface water into the public sewers, so gardens and soft/ permeable landscaping is used to absorb some of the water. Which means soggy gardens unlike it soaks away.

RelievedSheff

weeg said:

tim_london said:

If it's a new build - chances are there is a waterproof geo-textile sheet under the layer of topsoil.  Usually this is designed to stop groundwater flooding and contamination (especially if build on old brownfield site) from coming up.   The issue is this layer also stops water being soaked downwards, thus increasing chance of water logging.

I'm not a construction expert, but maybe you can research on feasibility of moving that layer lower?

Happily, I am something of a mass  house-builder expert. (I'm a engineer for a consultancy and that's 90% of our workload).

Waterproof geotextile membranes are only used as a last resort. It's more common to try and excavate, or remediate the ground if it's contaminated. If there is one under your garden (which is pretty unlikely) moving it would be a bad idea and would be unlikely to have any sort of good outcome.

The thing is, gardens are very much an afterthought to the houses. It's usually just a case of chucking down some subsoil and turf at the end of the build - 100mm or so. Beneath that it varies, depending on what was there to start with, but often there is a well compacted top layer from construction plant etc. Start with making a pattern of holes to see if you get through it to a more permeable layer. Beyond that, field drains are probably the answer.

In Scotland (where I work) it's almost impossible to get permission to put new surface water into the public sewers, so gardens and soft/ permeable landscaping is used to absorb some of the water. Which means soggy gardens unlike it soaks away.

Like in Scotland, in England ground water has no right of connection to public sewers so even if land drainage is installed in gardens then another suitable outfall has to be found.

Most boggy or waterlogged gardens in new builds will settle down once turf and planting are established. It is a very rare occasion that proper land drainage systems are required.

Newnoel

Might be worth considering planting trees or shrubs that thrive in wet conditions - we have a eucalyptus and a willow in one section of our garden that have really helped.
Some other ideas here:
Waterlogged lawns / RHS Gardening

fewcloudy

- Draughts - every door in the place has cold air leakage all around it, so I feel like they need to do something here, but unsure if they will....

I would hope that every door in the place (other than the main front/back doors) would have "air leakage" around them; internal doors aren't meant to be airtight!

tim_london

weeg said:

tim_london said:

If it's a new build - chances are there is a waterproof geo-textile sheet under the layer of topsoil.  Usually this is designed to stop groundwater flooding and contamination (especially if build on old brownfield site) from coming up.   The issue is this layer also stops water being soaked downwards, thus increasing chance of water logging.

I'm not a construction expert, but maybe you can research on feasibility of moving that layer lower?

Happily, I am something of a mass  house-builder expert. (I'm a engineer for a consultancy and that's 90% of our workload).

Waterproof geotextile membranes are only used as a last resort. It's more common to try and excavate, or remediate the ground if it's contaminated. If there is one under your garden (which is pretty unlikely) moving it would be a bad idea and would be unlikely to have any sort of good outcome.

The thing is, gardens are very much an afterthought to the houses. It's usually just a case of chucking down some subsoil and turf at the end of the build - 100mm or so. Beneath that it varies, depending on what was there to start with, but often there is a well compacted top layer from construction plant etc. Start with making a pattern of holes to see if you get through it to a more permeable layer. Beyond that, field drains are probably the answer.

In Scotland (where I work) it's almost impossible to get permission to put new surface water into the public sewers, so gardens and soft/ permeable landscaping is used to absorb some of the water. Which means soggy gardens unlike it soaks away.

Wow learn something new every day.  Glad I pulled out of the new build with that (and associated flood risk).