stylish living room

Converting your cellar or basement with drywall plasterboard to create new living areas

Are you looking to make extra space in your house?

The answer could be right under your feet!

A basement or cellar below a house is often an unloved and unused space but with a little hard work and knowledge, it can be transformed into a variety of things.

Whether you have a growing family, or just need a bit more storage space, converting your basement can be easier than you think, and the benefits to the you, and the value of the house, will astound you!

With a usable basement room, you can give your property some much needed extra space, more room for the family, and can even add extra value to the resale price of your house!

The cellar in your home is often a large un-used space beneath your house that could be used for loads of different things and if it is large enough, it can be sectioned using stud partition walls.

That can create several different rooms, in fact you could make a flat down there, and if a separate entrance is possible, and with a bit of extra paperwork, the flat can be rented or sold to generate extra income!

Converting your cellar with plasterboard.

What you do with your newly converted cellar is up to you and you needs, but popular conversions can encompass many different guises such as a music room.

This could be the perfect conversion if you have teenage kids, and a basement conversion, being mainly under the ground, much of the noise the little monsters make, will not be heard above ground, or next door!

Another great idea for your cellar, and possibly the simplest, would be to create A large storage space under the house for all that clutter you have accumulated over the years.

You can of course also create a large and separate bedroom which is good for growing up kids, or for when granny comes to stay! …..

(……Or even a a dungeon for the mother in law???)

mother in law
A cellar can be the ideal place for your mother in law to stay

The possibilities for your converted basement are endless, in fact it is only your imagination stopping you converting your basement now!

Basement conversions: what you need to know.

Now we have seen what is possible, what about the practical elements of the conversion, and more importantly, what about waterproofing that space?

Your cellar will be under your property, so the room will be under ground level or at least partly underground, so there are various factors to consider in doing the job, most importantly, the need for adequate ventilation and of course, keeping the space dry and damp free.

You also need to think about waterproofing the floor, to avoid damp rising up from the ground.

Damp, or moisture will rise up from the floor if a suitable sealant is not applied to the flooring in-situ.

If the cellar, as it is, feels damp-free, and it has never flooded, then possibly a DPM, damp proof membrane, may have already been installed in the floor, but its best to check, just in case.

Remember also, that if your home is in an area with a high risk of flooding, the best advice would be to not use the cellar as a habitable room, but as a storeroom, just in case, and have a think what action you would take if your home was flooded?

So with the floor sealed, it is time to begin work on the walls.

One of the most common ways of making your cellar dry and inviting is to add a second false wall, so to speak, over the wall surface and a popular way that has been used for some time is to install gyproc plasterboards, but special ones with have a waterproof layer on one side.

You can also use a special basement coating often referred to as tanking, and we will discuss that in a later article.

One of the major thing to think about when planning a basement conversion like this, is can you do it yourself, or do you need to hire a builder or a cellar conversion company to do the work as it is NOT an easy thing to do!

It is heavy, hard work, and often working below ground can be hot too, just think, because it is subterranean, it means the temperature will remain a constant in there, and if no ventilation is present, the work can be quite hot.

It’s worth noting that if you are claustrophobic, this really will NOT be your cup of tea, in fact if that’s the case, its perhaps a bit pointless having the cellar converted into a room as you wont use it!

Installing the plasterboard drywall.

To successfully install anti-damp plasterboards, you need to start by looking, or making a floor plan.

Then measure the height between the floor and the ceiling in order to work out how much in the way of building materials will be needed for the job.

Remember when considering doing it yourself, or hiring a cellar conversion firm, the fact that it is not only the walls that require work.

There are other factors in this project, such lighting and electrics, especially if non exists down there, and of course a major issue ventilation.

You may want an air conditioning unit fitted down there, or, especially if no windows exist, you may also have to provide some form of air extraction to the exterior.

If you fit an aircon unit, remember the high running costs of such a system. Heating may also be needed in the cellar.

Fitting drywall
Fitting drywall (C) This old house HGTV

Starting the work, batons, studs or wooden sticks need to be fixed to the existing walls in a set pattern, and then the plasterboard sheets are nailed in place or screwed into the wooden slats, like in the image here.

Look at the burly builders doing the work, this is heavy stuff and unless you are very experienced at this, and have physical strength, AND have a friend or labourer to help you, it is not something that the average person should consider doing.

In addition to the work actually installing the drywall, there will be a multitude of cables and pipes in the space, all of which need to go in behind the plaster walls.

Fitting out the services in the cellar.

The cables (lighting, mains supply, phone etc.) and pipes (gas, water, drainage, aircon) may also be something that you are not qualified to take care of.

If you also need to fit electrical sockets, TV aerial sockets, ventilation ducting etc, it sounds like you may need to hire a professional company to carry the conversion out, which of course will raise the price dramatically, but you can be sure the job will be done right!

After the fitting of the wall boards.

Once you have your room finished, well, the initial stage anyway, you also need to think about what paint to go on the walls and ceiling, internal fixtures and fitting (lights, sockets, sinks, doors, etc etc).

You also need to consider the choice of flooring; carpets are best because you can add insulation underneath them to combat a cold concrete floor, or laminated wooden floorboards.

Bear in mind, if the walls under the plasterboard are not also sealed at least with something, then the space between the walls and the plasterboard can quickly attract mould to grow

So again, this is something that a professional builder would be able to advise you on before you fit the boards to the walls.

As you can see, having a basement converted with this system brings many benefits to your home and lifestyle, but it is certainly NOT a simple and quick  job and time after time, the over enthusiastic DIY’er gives up and calls a professional builder or contractor, and that would of course be my advice to you.

Final thoughts and considerations when thinking about converting a basement or cellar into a usable space.

It is worth noting that increasing the square footage of your house will raise it’s market value, of course as long as the job is carried out correctly.

Remember also you must consider the rest of the house itself. It is possible to OVER develop a house, especially if the property is not located in desirable area.

You must also consider ventilation to the space, whether that is windows, extractor fans or air conditioning, the people using the space must be able to breathe once they are down there!

Heating is also something to think about although if a room is truly under ground level it often finds its own temperature, usually around 21 degrees, which is comfortable for most people.

ACCESS is also a main concern, you do not want to have to use a ladder to get in and out of the room, consider where a staircase would go, should it be a straight one or a spiral staircase, often handy for fitting into tight spaces.

Lastly, and worse case scenario consider SAFETY. There must not be a fire risk and you must also consider how people would safely get pout if there was a fire. What is there was a fire in the house above? How would you get out?

Think about building an opening out into the garden, even if just as a fire escape. It’s unlikely but you never know.

This is an original article by property surveyor Guy Alexander Bell. Bsc.(hons).Pg.Dp.

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