Converting Your Loft – Internal Space and Layout

In my last loft blog, I looked at the key structural elements that determine the floor area and volume of your loft conversion. This next blog looks at the interior, the space you can create and how you can make it work for you.

What Do You Want?

In converting your loft you’ll want to ensure you achieve the space you envisaged at the planning stage. What you can achieve will be determined by the floor area and the volume you can build (see earlier blogs on the exterior and structure).
If you are converting the loft in a small terraced house in a conservation area you may only have space for one room.
If your property is an Edwardian townhouse and has permitted development (PD) rights you should be able to build a full-width rear dormer accommodating one or more rooms plus a shower. A bigger floor plan could fit two bedrooms
If your home is a large Victorian semi with PD rights you could build a hip-to-gable and full-width rear dormer creating a big dual-aspect bedroom with an ensuite and a dressing room.

What Can You Create?

The Stairs & Landing

At the top of the new stairs to the loft will be a landing and its location will determine how well the loft works. The landing is only required to be as deep as it is wide but needs to be located to give direct access to the rooms in the loft. Corridors lead off the landing use valuable space and should be avoided.

All habitable rooms in a loft need must have fire door. If you only have one habitable room in your loft the fire door could be either at the top or the bottom of the stairs. Where there is more than one habitable room in the loft all habitable rooms must have a fire door directly on to the landing.
Ideally, the new stairs and landing at the top will have natural-light either from a window in the dormer or the side gable or from a roof light.

Usable Space in the Loft

Under the skieling (the sloping ceiling) and beside the dwarf walls in your loft, there will areas of the loft you can’t stand up in. You can use these areas for a chest of draws or for other low furniture. If you ask your loft designer to draw a line on your loft plan indicating where you can stand up (1.8m) you will have a good idea of the usable space in the loft.

Bedrooms or Other Habitable Rooms

You’re likely to be spending the most time in your new bedroom, office or chill-out room. I favour rooms with dual-aspect windows or roof lights, they give light from two directions, allow cross-ventilation and enable you to see out in two different ways. Your requirement may be for more rooms, which may prevent you having dual-aspect rooms.
In a good loft conversion, the new rooms feel part of the existing home. If the new stairs follow the existing this is easier to achieve.

Bathroom or Shower Room

What do you want, a bathroom with a bath or just a shower? The end of a bath can fit under the skieling, showers need full height ceiling but they take up much less room than a bath.
Generally, home-owners want to maximise the size of the habitable rooms and squeeze the bath or shower room in where they can. In an Edward terraced property, you can often fit a shower room behind the staircase.
It is desirable for a bath or shower room to have natural light and ventilation from a window or a roof light.

Dressing Rooms & Storage Areas

A dressing room with fitted cupboards and wardrobes can utilise some of the more awkward spaces you may have in your loft.
Dressing rooms and storage areas are not classed as habitable rooms so they can be inner rooms (not have direct access on to the landing) and can utilise parts of the loft where access and head height is limited.

Fire safety, means of escape

Building Regulations determine the fire safety and fire protection requirements for loft conversions. Whilst the regulations are national standards there are slight variations across Local Authority areas.
Conversion of the loft in a one or two-storey property where there is a protected means of escape from the new rooms should not impact upon the layout of the new loft space.
If the floor of the new loft space will be more than 7.5m from the ground level or the property has an open-plan ground floor or there is not a protected means of escape there will be design implications and limitations on what you can do. In such cases, it would be advisable to have detailed discussions with a specialist or building control before proceeding with plans.

The space you can create will be limited by the footprint of your home and restricted by planning legislation. The floor areas, the volume you can build, your wishes and building regulations will determine how you loft works.
The challenge for your loft designer will be to take these sometimes conflicting elements and come up with something that really works for you and give you what you want.

For details of my other loft blogs please check out my website:

Please note this is a guide and is not a definitive source of technical and/or legal information.

Converting Your Loft – Key Structural Elements

This 3rd loft blog looks at the key structural elements that will form your new loft. It is these elements and their interaction which will create the space in your loft.

The key elements that create the structure are;

New Loft Stairs

New stairs will be required for your loft conversion. Under building regulations the maximum pitch for new stairs is 42 degrees, all the steps have to be the same height and you need a minimum of 2m head height over the stairs. (There are some minor relaxations where the head height for new stairs to a loft conversion is limited.) These regulations will determine where the new stairs can go.
The location of the new stairs is critical, where the stairs finish in the loft will determine how well the new loft space works. In locating the new stairs the aims should be to; prevent the loss of any existing living or bedroom space in the floor below, to maximise the space created in the loft and to make the rooms in the loft work as efficiently as possible. To achieve this the stairs should ideally start on a landing or hallway and finish where you can create a landing with direct access to the rooms in the loft.
If the new stairs follow the line of the existing stairs this will be the best use of space. If you copy the details of the banisters and balustrades it will look as though the stairs have always been there. If your property has Permitted Development (PD) rights and you build a dormer, mansard and/or a hip-to-gable you should be able to achieve this.
If your loft conversion is subject to planning approval you may have to locate the new stairs under the ridge to satisfy building regulations. You might be able to get planning approval for a small dormer into which you can fit the new stairs. You will need a dormer with an external width of about 1.8m to achieve this.

New Floor Structure

The floors of loft spaces are only designed as ceilings. Ceilings are normally constructed from 50 by 100 joists (4” by 2”) and are not strong enough for new habitable rooms. You will need new deeper floor joists, which means the finished floor level will be higher than the existing.

New Roof Structure

Unless you are building a dormer, mansard or a hip-to-gable the existing rafters will remain in place. To maximise the internal space any purlins or bracing will be removed and replaced with a timber dwarf wall (about 800mm to 1m high). To ensure structural stability the remaining rafters are likely to need beefing up. Adding thicker rafters and the required thickness of insulation (100mm or so from the face of the existing rafters) will mean the existing roof is reduced in height.


A dormer will determine where the new stairs go. It can significantly improve the space and layout in your new loft, making the difference between a cramped space and one that feels like the rest of your home. Dormers usually have a timber structure and a flat roof but you can also have a factory produced modular steel framed dormer.


Mansard loft conversions are commonly seen in London where mansard roofs have been a feature since the Georgian times. A mansard roof has two sloping elements each side, the lower roof is at a steeper pitch than the upper. A mansard conversion involves raising the party walls and building a structure in between the walls. Mansard roofs do not give quite as much space as a dormer but are considered to be more attractive on period buildings.


Hip-to-gable conversions work well on properties where the existing stairs run along-side the gable end wall with a hipped roof above the gable (1930s semi-detached properties often have a hipped-end). A hip-to-gable would allow the new stairs to follow the line of the existing, it would give the required head height for the new stairs and allow space for a landing at the top of the stairs. A hip-to-gable combined with a dormer can create a really big loft conversion.

Converting the loft of the Rear Outrigger

A rear outrigger is an original extension at the back of your home at right angles to the main part of the property. If you have a loft over your rear outrigger and your property has PD rights converting it is a smart way to significantly increase the floor area you can create in your loft conversion.

External Materials

The finish and materials for a loft extension (a dormer, a hip-to-gable and/or conversion over the rear outrigger) will be determined either by the planning approval or by the PD rules for your property.
If planning approval is required your choice of materials will be limited by Council policy and by the type and status of your property. You may be required to match the existing materials or your Council may be more flexible.
If your property has PD rights the PD rules state that “the materials used in any exterior work shall be of a similar appearance to those used in the construction of the existing dwelling house.” Council’s may interpret this differently so check with your Local Authority.

The structures you can add to your existing loft will create the new loft space. What you can build will depend upon either planning approval or the PD rights for your property. When proposing big roof extensions under PD the PD rights can be quite complicated. If in double, seek professional advice and apply for a Certificate of Lawfulness for your proposals to ensure you do not breach planning regulations.

For details of my other loft blogs please check out my website:

Please note this is a guide and is not a definitive source of legal information.

Clean out the Gutters

Did you miss National Maintenance week, which ran from 17th to 24th November? I did too. The Society for the Preservation of Ancient Buildings (SPAB) runs a National Maintenance week every year. The SPAB week focusses on older buildings but much of what they say can be applied to your home. Maintenance is often low on the list of work to do to our homes. We all want to extend, convert and improve rather than protect what we’ve got. Results of the English House Survey 2015-16 show that 18% of owner-occupied homes failed to meet the Decent Homes Standard and 3% have damp problems.

Checking your gutters & gulleys

The SPAB maintenance week finished with National Gutters day. Next time it rains hard put on your wellies and a waterproof, go outside and have a look at your gutters and downpipes. Is there water streaming down the exterior walls or are the gutters doing their job? Inspect the gulleys at the bottom of the downpipes. Is the rainwater flowing away freely or is the gulley overflowing and potentially adding to damp in your house?

At this time of year gutters and gulleys can be blocked by leaves. If you have leaves in your gutters and gulleys, vegetation growing in the hopper heads or water streaming down the walls you really need to fix it.

Internal Damp

Whilst you’re checking, are there any damp patches inside your house? If you have water streaming down the outside walls there is likely to be a corresponding damp patch inside. Check around chimney breasts. An open chimney can cause falling damp – rainwater entering the chimney and wetting the walls below. Alternatively, the pointing or flashing on the chimney could have failed.

Check the Loft

If you can get into the loft can you see any signed of water penetration? Dampness to the chimney breast may be more obvious. Can you see light through the roof? If you can this is a sure sign some tiles have failed and that your roof is pretty old (newer roof will have a waterproof membrane under the tiles).

Symptoms and Signs

Mould has a distinct smell, we all know the aroma that hits us as we walk into a damp basement. Wet walls are often a different colour from the surrounding paintwork. Condensation on internal walls, often in the bathroom or other hot damp rooms, is indicated by black mould. Mould spores are bad for your health. Low-level moisture, possibly caused by rising damp, will cause emulsion paint to bubble and flake off.

Why basic maintenance is essential

Wet walls and structure damage the fabric of your home, they are bad for your health and leaving a damp problem will cost you more money in the longer term. High humidity in your home can lead to a dust mite proliferation, which causes asthma. Poor ventilation can cause a build-up of chemical compounds and /or mould spores, which can result in repository problems.

A damp free and well-maintained house is a healthier and more comfortable house. If you are planning to build an extension, convert your loft, renovate or carry out retrofit measures, ensuring your home is well maintained and damp free should be one of the first steps in this process.

For details of other blogs please check out my website:

Please note this is a guide and is not a definitive source of technical & legal information.

Converting Your Loft – Design Implications, the Exterior

In my 1st blog, we looked at the outline issues in converting your loft. This 2nd blog looks in more detail at the limits on what you can build and the resultant implications on the overall volume you could create.

Fixed physical boundaries

Your loft has fixed physical boundaries (the roof, the ridge and the ceiling below). These will ultimately be the limiting factor in the additional space you could create.
The extra space you can create by converting your loft will be determined by the size of the overall structure you are allowed to build and how much you can and want to push these fixed physical boundaries.
The size of the structure you are allowed to build will be primarily governed by whether you need planning permission or if can do the works under Permitted Development (PD) rights.

Unless you have other limitations (finance?) you may wish to go for the route that has the least ‘regulatory hoops to jump through’ and the one that should allow you to maximise the space you can create.

Planning Approval or Permitted Development?

If you need planning approval for your loft conversion the restrictions imposed upon you by the planning authority will limit the additional space you can create in converting your loft.
A loft conversion carried out under PD should enable you to exploit the full potential of your loft space. However, there are limitations when converting your loft under PD and you cannot do just as you want.

Planning Approval

Your Local Authority will have their own policies and design guidelines for converting lofts. Planning policies vary across the country but planning authorities do not usually support planning applications considered to have a visual and a negative impact on the roofs of properties. These will often include; alterations to the front roof slope, un-balancing pairs of houses by adding a hip-to-gable at the side and full width or box dormers to the rear roof slope.
You may be able to get planning approval for one or more small dormers, which will create more standing space in your loft. If you are lucky you may be able to get you loft stairs to fit into a dormer.

Permitted Development rights

Your Permitted Development (PD) rights for loft conversions are set out in a nationally produced document [link to doc].

Summary of the key PD rights for loft conversions

Any additional roof volume (including previous loft conversions) must not exceed: 40 cubic metres for a terraced house, or 50 cubic metres for a detached or a semi-detached house
No conversion works (except roof lights in the same plane as the roof slope) to extend beyond the plane of the existing roof slope that faces a road
Materials to be similar in appearance to the existing house
No part of the conversion to be higher than the highest part of the existing roof No verandas, balconies or raised platforms
Side-facing windows to be obscure glazed and non-opening below 1.7 metres
Conversions, apart from hip-to-gable, to be set back 200mm from the original eaves, measured along the roof plane

What can you do under PD?

Provide you keep within your PD rights, particularly the volume limitations, you can maximise the volume of your loft conversion by;
A Box Dormer. You can build a full-width box dormer to the rear roof slope of your home
A Hip-to-Gable. You can convert the hipped roof at the side of your home to gable
Convert the Outrigger loft. If you have a loft over your rear-facing outrigger this could be part of your conversion works

Interpretation of your PD rights

Interpretation of your PD rights can be quite complicated. If you are in any doubt or if you require legal confirmation you should submit an application for a Certificate of Lawfulness. A Certificate of Lawfulness is legal confirmation you do not need planning permission for the proposed works.

For details of my other loft blogs please check out my website:

Please note this is a guide and is not a definitive source of legal information.

Converting You Loft – Some Definitions & Information

To accompany my weekly blogs on converting your loft I enclosed some definitions of commonly used terms.

Building Regulations

Building Regulations are the minimum standards of design, construction, and safety that must be achieved when converting your loft. Building Regulations aim to create a safe, healthy and secure space. All loft conversions which create new habitable space must be compliant with building regulations.

Planning Permission

Planning permission is the formal approval of your Local Authority for the proposed alterations to the exterior of your property. Whether you need planning permission for your proposed loft conversion will depend upon the location, type, and status of your home and the works you wish to carry out. If you need planning permission for your loft conversion proposals you must get this before you start work.

Permitted Development rights

Permitted Development rights allow you to carry out certain building works without planning approval.

Certificate of Lawfulness

A Certificate of Lawfulness is confirmation that you do not need planning permission for the proposed works and that you can carry them out under Permitted Development rights.

Flats & Maisonettes

If you live in a flat or a maisonette you do not have Permitted Development rights and you will need to apply for planning approval to convert your loft. As a leaseholder, you should check you own the loft space (the details of ownership should be on your deeds). You will also need to obtain consent to the works from the freeholder of your building.

Designated Areas

These include conservation areas, Areas of Outstanding Natural Beauty (AONB), The Broads, National Parks & Word Heritage Sites. You have restricted or no Permitted Development rights in designated areas and will have to apply for planning approval to convert your loft.

Structural elements

Some definitions for structural elements found in typical lofts

Bracing – sloping timbers that support the purlins
Ceiling joists – horizontal timbers that hold up the plaster ceiling in the rooms below your loft space. They are designed for a ceiling and are not strong enough for a new floor
Floor joists – Horizontal timbers that support the floor. New floor joists are always required when converting a loft
Gable or gable-end – The vertical triangular upper part of a wall at the end of a ridged roof
Hip – The peaked part of the roof where two roof slopes meet. A hipped-end is typically found at the side of 1930s semi-detached houses
Hip beam – A sloping structural timber, which runs in line with the junction of the two roofs (the Hip) and that supports the roof load
‘Hip to gable’ – Where a hipped-end is converted to gable-end as part of a loft conversion
Purlins – large often square horizontal timbers that are at right angles to the rafters and that support them in the middle
Rafters – sloping timbers that support the tiles or slates on your roof
Ridge – The highest point of your loft
Ridge beam – A thin horizontal timber at the highest point of the loft. Pairs of rafters join at the ridge beam
Skeiling – The inside of a sloping ceiling, the finished underside of the rafters
Trusses – Structural elements running from the front to the back of loft that hold up the roof
Valley – A depression where two roof slopes meet creating a valley

For details of my other loft blogs please check out my website:

Please note this is a guide and is not a definitive source of legal information.

Converting Your Loft – The Basics

Converting your loft is one of the most cost-effective and space efficient improvements you could carry out to your home. You convert space you own and the basic structure is already there.

This is the 1st in a series blogs that share my knowledge and experience with you. Over the weeks I will go through the steps to help you establish; whether you can convert your loft, the potential restrictions and how to maximise the space you can create.

I did my first loft conversion 25 years ago on my own house in Manchester, since then I have designed 100s of lofts conversions for customers.

Rules and Regulations

Whatever you want to do and where ever you live there are rules and regulations governing what you can and can’t do if you want to convert your loft.

Building Regulations

All loft conversions which create new habitable space must be compliant with building regulations. If your home is over 3 storeys fire safety regulations may impose limitations on what you can do with your loft.

Planning Permission

Whether you need planning permission for your proposed loft conversion will depend upon the location, type, and status of your home and the works you wish to carry out.

Some Initial Questions

Can it be physically done?
Are there any restrictions that may limit your wishes?
How much is it going to cost, can you afford it?

Can it be physically done?

If you can answer yes to the following questions you should be able to convert your loft using the existing structure as a starting point.

I have got loft, which I can stand up in
I can stand up and put my hand up above my head below the highest point.
(I am about 1.73 m (5’ 8”) high and I can reach up to about 2.2 m, which is the minimum height required prior to works.)
Have a look outside. Have any neighbours with similar houses got lofts? Look for rooflights on the front roof slope or a dormer to the rear.

If you cannot answer yes to all these questions you may still be able to convert your loft but you will have to alter the structure.

There are no restrictions that may limit my wishes?

If you can answer yes to these questions you should be able to do a loft conversion under Permitted Development rights.
I live in a Freehold house or bungalow
My home is not in a conservation area, an AONB or a National Park
My home is not listed

There are restrictions that may limit my wishes?

If you answer yes to some of these questions you will not be able to convert your loft under Permitted Development rights
I live in a flat or maisonette
My home is in a conservation area, an AONB or a National Park
My home is listed

If you live in a flat or a maisonette you do not have Permitted Development rights and you will need to apply for planning approval to convert your loft.

Local Authority planning controls are stricter in conservation areas, AONB and National Parks. In these areas, a loft conversion will need planning approval.

If your home is listed, Listed Building Consent will always be required from the Local Authority for any works you wish to carry out to the exterior and to the interior of the property.

How much is it going to cost?

Try to find someone on your street (or a similar house in your area) who has had a loft conversion and ask them. There will be an element of guess-work setting your first budget. An initial sum of £30k is a very rough starting point. Increase the sum if it’s a big loft, take a bit off if it is very small.
Remember, any price given by a builder is exclusive of VAT so a quote of £25k will end up costing you £30k.
You will need money to cover the cost of decorating the loft and the new stairs and probably redecorating the landing as well. The loft rooms and stairs will need new floor finishes. If you have central heating you may need to replace your boiler to power the extra radiators required.

For details of my other loft blogs please check out my website:

Please note this is a guide and is not a definitive source of legal information.

Don’t Move Improve – Stay-put and invest in what you have

Don’t Move Improve! Convert your loft, build an extension, renovate your home, carry out internal alterations? This slogan seems to be back in the headlines.

Ideal Homes

A recent article in Ideal Homes is titled “Don’t move improve, is the home owner’s mantra after base rate rise”.
In the article, a survey of 1000 homeowners concluded that it was better to stay-put and improve their existing house. The article goes on to say that adding another bedroom and doing a loft conversion would on average add the most value to your home.

New London Architecture

New London Architecture is a forum for discussion and debate about architecture, planning, and development in London. They have been running a Don’t Move, Improve! competition since 2009. The competition celebrates London’s best and most innovative home extensions and improvements. The 2017 winner was a Japanese-style sunken bath tub encased in glass. The runners-up were an office in the garden and a light-filled extension with a courtyard.


A recent Halifax survey says that house prices are rising at the faster rate since January 2017, driven by lack of supply, historically low mortgage rates and high employment.

Cost of Moving

If you need more space or another bedroom and want to move you may find it difficult finding your ideal property. If you do find one and it costs over £1/2m, your moving costs and SDLT will be in the region of £25k.

Uncertain future

We live in times of uncertainty. Brexit, the continued rise in base rates (albeit very slowly), house prices, inflation, job security, the list goes on. Who knows where we will be in one or two years time?

‘An Englishman’s home (or occasionally, house) is his castle’

A historic and somewhat dubious statement but for all of us our home is a place of refuge, where (subject to appropriate approval) we can do as we please. More importantly, it is a place to live, to enjoy and to rest our heads. I have done 100s of loft conversions, extensions and alterations over the past 14 years and every one has loved what has been created. A good number have said, “why didn’t I do this years ago.”

Staying-put & Improve

If you improve your existing home you stay in the community. Improving your existing home uses existing resources as much of the structure is already there. If you specify a low energy build it will save energy (and your money) and be good for the environment. Improving your home benefits the local economy, you keep local trades people working.

A sunken bathing room in the garden is a fantastic option but perhaps a bit of a luxury for most of us. If you need more bedrooms for the expanding or returning family or if you want a family living area where you can all be together or just need another bathroom then maybe improving your existing home is the solution.

In 2008-09 I ran an advertising campaign, advertising my architectural services titled ‘Don’t Move Improve.’ It could be time to resuscitate the old slogan.

For more details of my work please check out my website:

Draft proofing a suspended timber floor

If insulating under a suspended timber floor is not possible, how can you stop the drafts between the floor boards?

Looking on the Web is a great way to research the best way of doing something. Caramel Quin wrote a great blog some time ago looking at ways to draft-proof stripped wooden floors.

Some timber and floor boarding companies had good blogs on the ‘filling the ‘gaps’ but many are for where you have not yet sanded the floor.

I thought seriously about using wedge-shaped pine slivers they are possibly the best and the most ‘green’ solution but I didn’t want to sand the floor again.

I needed to eliminate the draft but I wanted to retain the look of the golden pine boards broken by dark lines, which meant retaining the gaps. This stance eliminated using any kind of filler option, which can often fill both the gap and half the floor board.

Having considered all the options I opted for StopGap . It is thin V-shaped plastic on a roll that you push into the gap, down to the joist level and it opens out to fill the gap. It can be used to fill 1-8mm gaps in both floor boards and skirting boards. If you are going to re-varnish the floor this needs to be done before fitting the StopGap.  To ensure the StopGap works as efficiently as possible the gap between the floorboards need to be free from debris and any drips of old varnish cleaned off the sides of the floor boards.

I wanted to make the floor as draft proof as possible so to finish the floor I ran a strip of painted timber beading around the base of the skirting board and sealed this with an acrylic interior frame sealant.

The result; the ground floor is definitely less drafty and the room feels noticeably warmer.  The ‘under the floors board’ insulation option would have been better in terms of heat loss but it would have cost over £1,000. So I have stopped the drafts, kept my golden pine floor boards (some of which I have covered with rugs to give that real feeling of warmth) and the materials cost less than £150.

To move or to improve?

The housing market in the South East of England has always been strong but given the recent election, Brexit and events across the world we are in uncertain times and no one knows where the housing market will go next? It’s something we may ask ourselves when that inevitable question comes up “shall we put the house on the market and move or should we stay and improve?”

We all seem to need more space in our homes: an office at home is a work solution more of us are choosing and our families grow and need more room. Should we sell up and buy a bigger house, buy a property with development potential or improve our existing home?

Option 1: Move

Buying a new house is exciting. It gives us the opportunity to live in a new area, to see the town where we live from a new perspective and to meet new neighbours. Buying a new house can also bring new development opportunities, there are always properties advertised for sale that are ‘ripe for improvement’. You may also decide to move to a smaller home to reduce your outgoings.

Moving house is also one of the most stressful things we do; hopes and dreams can be dashed at almost any stage in the process. There is a substantial cost to moving. Dependent upon the value of your home, you’re unlikely to get much change from £20,000 just to move, and the costs could be much higher.

Option 2: Improve

Staying put and improving your existing home may not be as exciting, but it’s unlikely to be anything like so stressful. The £20,000 or more you would pay out just to move would go a long way to converting your loft or building an extension.

Whilst you home must firstly be the place you live it’s likely to be your most valuable asset and you may as well make the most of it. So it’s worth think about how you could improve your current home. Before you call the estate agent ask yourself “do I have to move, do I just want to move or could I stay put in my current home?”

Whichever option you choose, making the most of the development potential of your home is probably the most cost-effective way of increasing your living space.

Interested in option 2? Contact me for a free consultation on what could be possible with your current home or the development potential of your new one.

Insulating a suspended timber floor

My next task was to insulate the suspended timber ground floor.

I calculated that the gaps between my floor boards was equivalent to a hole 800mm by 800mm, no wonder it felt drafty. The floor boards on the ground floor are the original ‘pine’ boards, a beautiful golden colour. I wanted to retain them as a feature of the house so the only option was to insulate underneath them. The two ways to achieve this were either to lift all the boards and insert the insulation from above or get under the floor and insert the insulation from below. The floor was fixed firmly, it had been sanded and varnished already and lifting all the floorboards would have caused a lot of breakages and require re-sanding. The only option was to insulate and draft proof from underneath.

I removed a couple of boards in the hall, donned a boiler suit, goggles and face mask and squeezed under the floor – I could just move around, so it may be possible.

I now had to determine exactly what I needed to do. The Web has a number of good links covering insulating under a timber floor.–insulating-suspended-timber-floors.html

The aim is maximum insulation between the floor joists, using a fibrous insulation material that takes up the imperfections in the timber and that minimises the air movement around the insulation. The other objective is to stop the movement of air through the insulation and into the room but allow water vapour that may build up to escape. In addition; the insulation should not come into contact with any masonry walls but the gap between the joists and the foundation walls (usually about 50mm) needs to insulated and made draft proof, the air bricks from the outside need to be kept clear, cold water and central heating pipes below the insulation level need to be insulated (the void below the insulation will be much colder) and any electrical cables need to be prevented from overheating and kept free of insulation.

I needed to establish categorically if I could do all of this from underneath. There is a 400mm space between the bottom of the joists and the ground level but the joists rest on 100mm timbers so the working height is 300mm. I had to be able to crawl around underneath the floor for several hours completing the insulation and draft proofing work. I donned my boiler suit, goggles and face mask and after ten minutes established that 300mm was not sufficient room to do what was required – back to square one.