Basement Design - Options and features

Basement Insulation


You should only need a small radiator in a well insulated basement.
If the room is 100% underground, there is much less heat loss.
The planners can provide you with a U value that is required,
such as the current 0.2 W/m2k U-value.

SuperFOIL can provide a very thin foil based insulation
that can achieve the desired U value without the bulky loss
of space you normally associate with wall insulation.

Placed between 2 battens for example, the foil insulation
can expand to fill the gap between the P8 covered outer walls
and the foil backed plasterboards.

The multiple layers of foil prevent the transfer of
cold from outside getting in and the heat from the inside
getting out, with the minimum amount of space used.

Unfilled cavity wall (pre to 1900) have a U-value of 2.0 W/m2k
Unfilled cavity wall (1900 – 1975) have a U-value of 1.6 W/m2k
Unfilled cavity wall (1976 – 1982) have a U-value of 1.0 W/m2k
Unfilled cavity wall (1983 – 1995) have a U-value of 0.6 W/m2k

Filled cavity wall (1996 – 2002) have a U-value of 0.45 W/m2k
Filled cavity wall (2003 – 2006) have a U-value of 0.35 W/m2k
Filled cavity wall (2006 – 2010) have a U-value of 0.3 W/m2k
Filled cavity wall (2010 - 2020+) have a U-value of 0.2 W/m2k

Basement insulation

Placeholder Picture

The insulation puffs up between the 2 battens

Placeholder Picture

We use SuperFOIL insulation

Placeholder Picture

Reflective foil insulation

Placeholder Picture

The walls can be insulated to 0.1 W/m2k with multiple layers

Block foundation walls

Block step removal

The block steps are there to provide support for the cellar walls.
They are a block of weight to prevent the walls from moving sideways.
The fronts are usually bricks laid on the floor, not sunk into the floor
and they are usually back filled with loose rubble.

We remove the big old, bulky, loose rubble & brick steps &
replace them with reinforced concrete pins only 6 inches wide
which are sunk into the floor unlike the old steps.
We then pour the concrete slab to fix the new pins into position.

The new thin support is much smaller but much stronger.
It cannot be moved as it is now part of the concrete pad.

foundation walls

Placeholder Picture

The large loose rubble is removed

Placeholder Picture

The space is revealed - but needs reinforcing

Placeholder Picture

The new solid wall is sunk into the new concrete pad

Placeholder Picture

Now the room is warm, clean & useful for many years

Spindles & Light

Spandrel panel removal

The spandrel forms an air tight cover for the basement staircase,
preventing light or fresh air to enter the basement.

Now that your basement is going to be fresh and inviting,
you may want to open up the staircase.
You can add spindels in a traditional house
or go for a glass feature in a modern house.

We remove the spandrel and repair the surrounding area.
We can either fit a newel post, handrails and spindles
or an oak and glass stairwell for example.

from a closed panel to open spindles & light

Placeholder Picture

The basement was sealed and ingored

Placeholder Picture

Now it is revealed and inviting

Placeholder Picture

The hall is closed off and norrow

Placeholder Picture

Now it is inviting you to discover another room

Underfloor heating pipes

15mm pipes for heating

Whilst a screen floor is being laid over the insulation,
we could install a loop of 15mm pipes ready
to be used for underfloor heating in the future.

It would be too late to install the pipes needed for the
underfloor heating after the floor has been laid.

It does allow for the option of underfloor heating
to be used later if you want.

You will need the pipes to be buried in screed.
You would need a plumber to install a manifold and pump,
which could be powered from a local radiator.

underfloor heating pipes

Placeholder Picture

The pipes are laid with 200mm of spacing

Placeholder Picture

The whole floor is covered

Placeholder Picture

It should be sunk in thermal liquid screed to 70mm+

Placeholder Picture

The pipes are connected to a manifold and pump

Solid or floating wooden floor

Screed or wood?

All basements should have a solid concrete pad
with an imprint of a drainage system on it.
The sump is the lowest point, followed by the drains.

Over the pad, you should use a 20mm drainage membrane
which allows a head water to be dealt with by the pumps.

Now you have a choice, but each layer adds a cost;
- 22mm floating tongue & grove chip boards,
- 50mm foil backed, closed cell, tape joined insulation,
- 70mm self levelling thermal screed
in which you can fit 15mm underfloor heating pipes
and finally
- a latex based floor leveller, ready for a great tiling finish.

note that the pipes need to be fixed to the foil backed insulation
so both the insulation and screed at 120mm or 5 inches are required,
which with the 20mm membrane, will lift the floor by 6 inches.

Solid floor & liquid screed

Placeholder Picture

You must have a solid floor under tiles

Placeholder Picture

You must have a solid floor under utility areas

Placeholder Picture

You must have a solid floor with underfloor heating

Placeholder Picture

Solid floors for utility, gyms & tiled areas

Saniflo waste water systems

Underground plumbing systems

The basement pump cannot be used for frequent waste.
Waste water contains soaps, bleaches and effluent,
which can damage the membrane seals.
A separate plumbing system must be used.

Saniflo systems are specifically designed
to remove waste water from difficult areas;
pumping up to heights and lengths required for basements.

We recommend the Saniflo Sanicubic 1
You will need 2 x 50mm pipes to exit the building,
1 50mm pipe for waste to be connected to the foul drain &
1 50mm pipe for foul air, to be mounted in the air.

The Sanicubic can cope with washing machines, sinks and toilets,
which makes it ideal for a basement utility space.

Saniflo  sanicubic  1 waste pump

Placeholder Picture

This is how to get waste water out of a basement

Placeholder Picture

Waste water including soaps, bleaches & effluent

Placeholder Picture

Waste water to the sewer pipe, waste air vented outside

Placeholder Picture

Powerful enough for several toilets, washers and sinks

White washed walls

Pre decoration wash, sand and fill

A finished plaster wall is not 100% perfect.
When the plaster dries, it will become dusty.
There will be some areas that will need to be filled or sanded.

You shouldn't paint dusty walls.
Painting will highlight those small blemishes that need filling.

We can wash, sand down and fill your new plastered walls
to a white wash finish so you can decorate in confidence.

White will be the perfect base for any future colour.
White makes it easy to spot any problem areas,
which we will repair so you can decorate quickly.

Sand, fill and White wash - pre decoration

Placeholder Picture

Fill around plugs, lights, corners and skirting

Placeholder Picture

Removing any blobs, especially around the skirting

Placeholder Picture

Removing plaster dust that turns the paint griany

Placeholder Picture

Sanding and filling the face and corners, over and under

Light well & planning

Planning permission for light wells.

You may need planning permission before installing a light well, or
if you want to expand an existing window or light well.

We can complete the planning request for you.
We will need to produce drawings and location maps for you.

We can then install the lintels and window that tie into your basement.
The base of the light well should be a small soak away.

There are insurance rules and declarations to consider as well, as
the wrong window can cause you problems with your insurance later.

Light wells, temporary access & trickle vents

Placeholder Picture

Secured from unwanted visitors - 250mm wide

Placeholder Picture

Natural light and trickle vents in dark corners

Placeholder Picture

Natural light is the best light in a basement

Placeholder Picture

Temporary access can be gained using a large window

Cupboards & Storage

Building bespoke cupboards & storage

Now that you can store things in your basement
without them going wet, doesn't mean you want to see them.

We can also cover up some unwanted features
like the consumer unit, gas meter or incoming electricity supply.
using bespoke cupboards to form a flat surface.

We usually use 3x2 frames and MDF for the doors,
which can be replaced for glossy doors later,
now you have the bespoke door sizes you need.

Strong, bespoke, storage cupboards

Placeholder Picture

The gift of dry storage

Placeholder Picture

Huge cupboards to cover the plumbing - whilst allowing access

Placeholder Picture

Tiny cupboards to cover the meters - whilst allowing access

Placeholder Picture

Tested to be strong and fitted to your space

The utility room

Utility, tiling & drainage facility.

You may want to push the washer & dryer downstairs.
It would be useful the have a sink, toilet and a shower too.

You are going to need air extraction &
I would also strongly suggest a drainage system.
There may not be anything as bad as a utility flood, in a basement,
especially on a wooden floor.

For utility areas, with washers, toilets and sinks,
we suggest a tiled floor with a drainage point, like a wet room.
You don't have to worry about any floods that may occur
as you will have a utility drain you can use.

Utility, tiling & drainage

Placeholder Picture

The utility floor has been laid up to the drain point

Placeholder Picture

The floor has been tiled wall to wall

Placeholder Picture

The tiles link to the wide drain point

Placeholder Picture

The complete package, utility & wet room floor

Soak Away

A 2M sq soak away per pump.

Council's don't like you to add new water
to an already overloaded drainage system.
Clean water from the ground or rain can be
sent to a soak away in your garden or drive.

Building regulations may state the requirement
of a soak away to be installed.

A soak away can become a strategic asset for your property,
future proofing you from future planning permission applications.

We suggest a 2 meter squared hole with either round stones or
a soak away crate can be used, 2x (600mmx600mmx690mm) crates,
covered in a porous sheet, buried in the stones will allow
substantial drainage to occur, compared with soil or sand alone.

Soak Away - external drainage

Placeholder Picture

This is a pourus pipe in a huge soak away trench

Placeholder Picture

The pipe carries mass water to a deep soak away

Placeholder Picture

This deep soak away will take the basement water

Placeholder Picture

The hole is 2 M square filled with round stone