Can I use my flat roof as a terrace?
Having outdoor living space is an important consideration for modern homes. With space often at a premium, especially in urban locations, a roof terrace will allow you to make the most of an otherwise unused area and provide a desirable outdoor space, perfect for entertaining, growing food or just enjoying the fresh air and sunshine.
When creating a roof terrace, there’s a lot to think about to ensure the space is safe, easy to access and meets the requirements of the homeowner. Here are some things to consider:
Roof type and structure
The type of roof will play a defining role in how the roof terrace is constructed.
For obvious reasons, a sloped roof is not an ideal candidate for a roof terrace. However, flat spaces can be created either by building up an external wall or cutting into the roof. Getting planning permission for this type of project can often be difficult.
In most cases, an existing flat roof will be used to create a roof terrace. In concrete or steel frame buildings, the existing flat roof is likely to have enough structural strength for a terrace, because the roof is constructed like the floor structures below. Timber-framed residential constructions are much more likely to require upgrading. This will usually entail placing a steel joist underneath the roof structure.
Whatever type of roof the property currently has, a structural engineer will need to survey the property and drill inspection holes to determine how the roof has been built-up and what upgrades will be required to ensure the roof meets the necessary structural and loading requirements.
It’s important to remember that attributes such as waterproofing, drainage, insulation and fireproofing are all dependent on the entire system, rather than individual components. Any change to the roof’s construction could affect its performance in these key areas.
To ensure the property conforms to the building regulations and other standards, you will need to work closely with a variety of experts and also consult product manufacturers.
Questions to ask when planning a roof garden include:
- Will the space be used by children?
- Will pets use the space?
- How much time will be spent on the roof terrace?
- How can you maximise the best views?
- Will you need walk-on roof lights for lighting up the space below?
- What kind of lighting will be required?
- What’s the microclimate like?
During the early stages of the planning process, the design team should work with the homeowner or developer to determine what is expected of the finished roof terrace and how it will be used. It’s also important to consult a landscape architect as soon as possible to ensure the roof is technically capable of dealing with the various elements they plan on adding to the space.
No garden? Create a roof terrace with these tips
There’s talk of the current heatwave in the UK continuing until October. And while this will come as welcome news to many people across the country, those without gardens may be feeling as though they are missing out on opportunities to make the most of the good weather.
Other than going to a local park, a nearby beach or around a friend’s house, what alternatives are there if you want to enjoy the sunshine but don’t have a garden at home?
The solution could be creating a roof terrace or roof garden for your home. A flat roof offers the perfect opportunity to build roof terrace without breaking the bank. Whether it’s a flat roof on a house, garage, extension or top floor penthouse. These tips will help you to plan how to create a roof garden or terrace.
1. Is your roof suitable?
Before you start considering design options and creating an image of your finished roof terrace in your head, you need to determine whether your walls and roof can take the weight of one. After all, a roof terrace alone adds additional weight and this is increased significantly once furnishings and fittings have been added and people are walking around on it.
It’s best to a surveyor to take a look for you to advise you on what can and can’t be done and any building regulations etc.
2. Do you need planning permission?
You almost certainly will. That’s because adding a roof terrace will involve some major surgery on your house. Moreover, if your terrace will overlook neighbouring properties, securing planning permission is almost certainly a must. Going ahead without checking the required planning permission requirements and you could end up in a very difficult situation if someone complains, or you want to sell the property. If you live in England, contact your local planning authority (LPA) in the first instance and take it from there.
3. Be a good neighbour
Even if your roof terrace doesn’t require planning permission, it’s still best to be a good neighbour and discuss your plans with the people who live near you. It’s a simple gesture of goodwill that could prevent any complaints in the future. Your new roof terrace may overlook their property and impact their privacy and during the building work, there is likely to be some noise and disruption. The bottom line is being open and honest with your neighbours is likely to stand you in better stead going forward.
4. Consider drainage
We’re sorry to say the gorgeous weather isn’t going to last forever, so you need to seriously consider how rainwater is going to drain from your roof terrace. Even though most appear flat, roof terraces slope very slightly and drain into one corner.
Check to see if you’ve got an existing downpipe that your roof terrace can drain into. If you haven’t, one will need to be added or you’re going to end up with a rooftop swimming pool instead –hmmm, now that’s an idea!
5. Install some windbreaks
Your new roof garden is going to be quite a bit windier than a regular garden. For a start, it’s unlikely to have any buildings providing it with cover. That’s why you’ll almost certainly need to install some latticed windbreaks.
Converting your flat roof into a terrace, balcony or roof garden
Would you like to create more outside space but you’re not sure where and how? Do you have a flat roof? If so, you could soon be enjoying additional outdoor living and entertaining space!
It is far easier than you’d think to convert a flat roof into a terrace or balcony – you just need to have the right materials. For example, what is your existing flat roof made of? If it is constructed of traditional felt, attempting to upgrade it into a terrace or balcony is not recommended. Flat felt roofs have a short life span – many house insurers refuse to cover older felt roofs. Over the years, they are affected by the elements, blistering, cracking and attracting moss and algae. The last thing you want is to construct a beautiful new outside living space, only to find that it needs to be dismantled so that you can access the felt to make repairs.
You will be expecting your flat roof to bear more weight, which means that you must consider the implications of this extra load before building commences. By engaging the expertise of a structural engineer to advise on how your flat roof can support whatever materials you decide to use – patio slabs or decking – you can save yourself a lot of hassle and money further down the line.
What’s the best solution?
It is recommended that you install a uPVC membrane roofing system before you start any conversion. The benefits of this short term initial expense will far outweigh the drawbacks of building on a sub-standard felt roof.
High-Tech Membrane Roofing’s recommended Single-Ply membrane flat roofs provide first class protection against the elements and if you buy through us, you will enjoy a rock solid, no quibble LIFETIME guarantee.
Once you have prepared your conversion with a high quality roofing solution, you will need to protect the membrane by waterproofing it. Usually, this is in the form of plastic or rubber paving support slabs. These slabs have the additional benefit of allowing water to drain away with ease.
Considering a roof garden?
Are you thinking of utilising an unused flat roof into a roof garden? Here are our top tips:
- Investigate support issues before construction – will you need walkway pads and slabs?
- Ensure your home remains waterproof by installing a flat roofing membrane
- Consider drainage points
- What sort of roof garden do you want? You could choose a green roof, decking or artificial turf
Whatever outside space you choose to create, please be aware that you are legally required to install a permanent handrail with any flat roof terrace, balcony or garden.