Polished concrete floorıng

A great way to bring a stylish contemporary aesthetic to your home — read on to find out more about this versatile and hardwearing flooring option.

Polished concrete is not just a material used by those after a super-contemporary industrial look — new techniques and finishes means it’s now being used by those after all kinds of interior schemes, looking for a sleek, easy-to-care-for floor.

Polished concrete comes in a variety of colours and finishes and is perfect for use with underfloor heating, too — as well as being a good retainer of heat. Polished concrete flooring is achieved using concrete – cement, gravel, sand and water – with chemical densifiers added to it. These densifiers act to fill the holes and pores in the concrete. The poured concrete is then ground down with diamond polishing tools, which get progressively finer until the level of sheen and smoothness you are after is achieved. And despite some common misconceptions, it need not look or feel cold.

ADVANTAGES

Polished concrete has a lot of benefits, including being:

● A smooth and sleek flooring type that suits the minimalist interiors of many contemporary homes.

● A low-maintenance, easy to clean flooring. This flooring is perfect for households with pets and in rooms with high levels of foot traffic as it is extremely hard and durable and simple to keep clean.

● A non-slip finish. Despite its ‘sheen’, polished concrete is a non slip type of flooring, which makes it ideal for use in kitchens, bathrooms and utility rooms.

● A seamless look between inside and out. Polished concrete flooring is also suitable for exterior use so is ideal where a level threshold is required between indoor and outdoor spaces, for example where bifold or sliding doors have been incorporated into a design.

● Underfloor heating. Concrete is an excellent heat conductor and is easy to pour over an underfloor heating system.

● A floor that benefits from solar gain. In spaces where the sun is allowed to shine in, a polished concrete floor will absorb and hold the heat well; this is especially the case in south-facing rooms

You should be aware that polished concrete floors will occasionally require resealing. There are a range of stain-removal treatments and aftercare products available to keep your floor looking its best. “However, a polished concrete floor is designed to last a lifetime with very little maintenance required,” points out Ben Young of polished concrete specialists Lazenby.

COLOURS AND FINISHES

If you are looking for a bespoke look for your flooring, polished concrete can deliver — no two floors will look the same, thanks to the natural colouration and distinctive patterning found in each installation. Polished concrete floors suit contemporary interiors well, and can add a modern accent to more traditional designs, too. And by choosing a glossy polished finish, your flooring will look more like a stone tile.

“We have a range of 15 standard colours but bespoke colours matched to RAL numbers are also possible,” says Ben Young. “Every floor is available in a matt, satin or gloss finish depending on the level of sheen required. It is also possible to expose the natural aggregates within the concrete through diamond polishing.”

TYPICAL COSTS

As a guide, a new polished concrete floor, poured, finished and sealed, will cost around £120/m²-£150/m². If you have an existing concrete floor that you wish to have polished, the cost will be approximately £50/m².

There are several factors that will influence what you pay:

● the area you are in

● the quality of the existing floors (in renovations) and whether any repairs are necessary before work can begin

● the size of the house

● the type of finish you are opting for (those with exposed aggregate finishes will cost more).

If those prices are outside your budget, consider concrete-effect porcelain tiles that typically cost from £20/m².

INSTALLATION METHODS

The most common way for a domestic floor to be poured and finished is using the ‘flooded bay’ method. According to Ben Young, the largest area or ‘bay’ Lazenby can pour is 5m x 5m. For areas larger than this, inducement joints will be cut in the day after the floor has been poured, using a neat saw.

These joints will also be used in doorways. They create a weak spot, meaning the concrete will shrink and crack in a straight line. This joint can then be filled with a flexible sealer such as polyurethane in a similar colour to your floor.

● The ready-mix concrete will be poured on site, usually reinforced with steel mesh and fibres. This mesh is used to minimise the risk of the floor cracking. The concrete should be poured after insulation and underfloor heating has been put down to a depth of 100mm.

● The whole space is filled and levelled using a laser, rakes, vibratory screeding machines and bull floats. Once the surface has been screeded, colour, if required, is applied to the surface. Over the course of the day, the concrete surface is refined and flattened using hand floats and power floats.

● The final surface is closed off and densified by hand trowel and/ or power trowel machines. This brings the cement paste to the surface, smoothing and hardening it until it develops a sheen. This can take anywhere from four to 14 hours, and partly depends on the weather conditions: too cold (5°C or lower) and fresh concrete can be permanently damaged; too hot and there is a risk of the concrete shrinking.

● Once poured and prepared, the concrete will need to be polished and sealed — something that must be carried out at least a month after pouring.

● Polishing either comes from cleaning and buffing the floor with a scrubbing machine or, better still, light diamond polishing to remove minimal laitance to bring out a medium sheen. For highly polished floors, the surface can be further enhanced using diamondencrusted flexible buffing pads.

● The floor will then need to be sealed. A penetrative sealant that allows the concrete to breathe is used for this.

Some suppliers offer alternative, although less commonly used, methods of installation, for example where the finished floor is poured as a ground-bearing slab. These floors usually have a minimum thickness of 150mm and come with heavier reinforcement.

The floor is poured onto wellcompacted MOT Type One (an easily compacted aggregate), blinding sand, DPM (damp-proof membrane) and insulation. A polished screed already has the ground-bearing slab in place and is poured over the insulation sitting on the slab below.

The polished ground-bearing slab has the added advantage of producing the finish in one go, but will have to be poured earlier and may suffer damage as other heavier work is carried out afterwards.

SCHEDULING THE INSTALLATION

When building from scratch, or using polished concrete when building an extension, the majority of in-situ polished concrete flooring is put in place prior to doors and any door tracks that may be fitted.

It is possible to produce the floor with these elements in place, but there is a great risk because cement corrodes aluminium and the process is not a delicate one. Doors can also cause a hindrance to the contractor and do not allow for threshold details to be incorporated.

A 10mm-thick brick-foam material is fitted to the perimeter of the floor to allow for any movement. This needs to be hidden by skirting or similar, so the floor must be poured before this stage of decoration, too.

In the case of shadow gaps, recessing it behind the wall build-up will hide the expansion material, and the floor should then be poured before the final wall finishes are built out.

Any partition walls, kitchen units and other structures should ideally be constructed on top of the finished concrete floor.

It is not necessary for windows and external doors to be fitted prior to fitting, but the inside should be protected from the elements in extreme weather and cold.

INSTALLATION TIME

According to Ben Young, “a concrete floor will be installed in three days. This includes all setting up and the final protection layer.” The concrete must be left to cure sufficiently before the grinding (polishing) process can begin, which is 28 days, generally.

SOUNDPROOFING A CEILING

Soundproofing a ceiling can be key to your enjoyment of spending time in your home. And it’s not something that only applies to those living in flats, either — if you live in a terraced or semi-detached house you might also find yourself plagued by noisy neighbours or lodgers. Even those living in detached homes may have to endure noise transfer from upstairs (teenagers playing loud music or children running around, for example).

Here’s all you need to know about soundproofing a ceiling, no matter what types of ceiling or home you have.

Before you can find the right soundproofing and noise control solution for you, think about:

● The type of noise you are trying to stop

● The type of ceiling you have

● Whether the noise is coming from above or below

● How loud the noise is.

Once you’ve answered these, you’ll be better placed to understand the options available and how they can solve the issue. And for soundproofing to work well, the right systems must be selected and it’s crucial they are fitted correctly. Ian Baker from The Soundproofing Store agrees: “Soundproofing is just like waterproofing — it’s only as good as its weakest point. Think of a car window. Even if it’s open just a tiny bit, you get all the noise from outside coming in.”

DIFFERENT KINDS OF NOISE

Firstly, it’s important to ascertain the kind of sound you are faced

with. “There are two types of sound that need to be dealt with when it comes to soundproofing a ceiling: airborne and impact,” explains Ian Baker.

“Airborne is the type of noise created by talking and sound of the television, for example. Impact noise, on the other hand, is caused by footfall, such as people running or walking around or items being dropped.”

The soundproofing measures required to stop the transfer of these different types of noise are not the same.

“To prevent airborne sounds you need to add extra mass to the ceiling, while to reduce impact noise you need a dampening system to absorb the vibrations,” explains Ian.

“The higher the decibel (dB) figure for airborne noise, the better, while the lower dB figure for impact noise the better. It’s usually necessary to address both airborne and impact noises.

TYPES OF CEILING

Your next consideration should be the type of ceiling you have: timber joist or concrete. “Concrete ceilings tend to have a high level of mass and density, which should already reduce a good level of airborne sound,” begins Mike Cunningham from Noisestop Systems. “With concrete ceilings, impact sounds will transmit through this material. Timber ceilings that have not been soundproofed often have both impact and airborne sound transfer between floors.”

Although the solutions for each type of ceiling are different, in general, there are three main aspects to soundproofing: adding mass, incorporating a material to absorb sounds, and creating separation.

● Mass: The higher the mass, the more you will reduce airborne sound. High-mass products such as acoustic insulation, soundproof plasterboard and mass-loaded vinyl will significantly reduce airborne sound.

● Absorption: This refers to the ability of the ceiling to absorb sound. Acoustic insulation between ceiling joists will help absorb sound as it transfers between floors. Empty ceiling cavities will often act as a drum, and the sound will resonate inside the cavity and amplify the sound.

● Isolation/separation: Creating isolation within the structure of the ceiling will reduce vibration. As the impact and airborne sounds transmit through solid surfaces via the vibration, it is essential to isolate the existing ceiling from the new soundproof ceiling.

TIMBER CEILINGS

In general, the approach to soundproofing a timber ceiling involves a combination of insulation, metal rubberised clips to absorb vibrations, metal channels or battens, and perhaps vinyl or rubber panels and a couple of layers of acoustic grade plasterboard. “The majority of our clients have timber joist ceilings,” says Ian Baker. “When we soundproof timber ceilings we need to create a sealed chamber which will absorb vibrations.

“First we add acoustic mineral wool insulation. Once the insulation is in place, metal rubberised clips are attached to the bottom of the joists, before ‘furring bars’ or ‘furring channels’ (metal battens) are fixed to them to take the new plasterboard.

“Next you need to add mass to deal with the airborne noise. We use two layers of acousticgrade plasterboard, using a rubber sheeting, called TecSound, between them. The aim is to use a combination of several high-mass materials for the best results — rather than lots of the same layers. Using this kind of system, you can expect to lose around 60mm of ceiling height, but you should get a 75% reduction in noise.”

CONCRETE CEILINGS

Here a different approach is required. “Because concrete ceilings already have high levels of mass, it is customary to treat these ceilings for impact sounds from above,” says Mike Cunningham.

“However, if you have plenty of height in the room, you could consider installing an independent ceiling. This type of ceiling does not touch the original and requires new ceiling joists. It does not require too many specialist products as the ceiling being independent is the key element.”

However, the most common method of soundproofing a concrete ceiling without losing head height is to use a system of products fixed directly to the concrete ceiling. “In an ideal  world, a new suspended frame would be built below the concrete ceiling to decouple it from the original structure,” says Ian Baker. “Our standard specification is to use our ReductoClip system directly to the concrete ceiling, resulting in only a 60mm loss of space. Mineral wool is also added in between the first layer of plasterboard and the original concrete ceiling, to stop any sound from amplifying within this space.”

When soundproofing a concrete ceiling to block out noisy neighbours, the sound can also travel down the walls so it is worth doing an ear test, listening for any noise coming through the walls. If this is the case, then soundproofing the wall will also be required.

THE CEILING LIGHT EFFECT

So does having ceiling lights affect soundproofing? “Think of sound like water in a bath — if you pull the plug out, all the water escapes,” explains Mike Cunningham. “Sound works in a similar way; if you leave even a small hole or gap, it will compromise the level of soundproofing.”

For this reason, you want to avoid cutting any holes in your ceiling to take new lights. Surfacemounted spotlights or pendants are a better option where sound travel is an issue.

THE COST FACTOR

This will largely depend on the size and type of your existing ceiling, and your approach. Based on a ceiling size of 4m x 4m, using a product such as the ReductoClip ceiling system, materials would cost around $1,800 - $2,000,

Another factor is whether you choose to do the work yourself. Many soundproofing kits can be fitted by a competent DIYer — but some of the elements are very heavy and so this is a job for two people.

Alternatively, you’ll find most soundproofing specialists will have a list of trusted installers.