The roof of a historic building is one of it’s most striking features and may have survived in a remarkably unchanged for condition for many centuries.

Roof Structure

Unless there has been substantial water leakage, the roof structure will usually be in good condition. This is often due to the generous amount of ventilation in historic buildings and their roof-spaces. Even though a historic building may generate a lot of internal moisture, some of which finds its way into the roof, it is quickly removed. Th moisture-buffering effect of the large amounts of hydroscopic material n many historic buildings ca also be helpful.

Pitched Roofs with Ventilated Roof Spaces

For traditional roofs with “cold” roof-spaces ventilated by outside air, it will often be possible to lay insulation over ceilings or between floor joists in the conventional manner.

Air infiltration into the roof-space from below should be reduced. In particular, holes around pipes, ducts and cable routes should be closed up, especially when they lead to areas of high humidity. Even then, some air and water vapour from the building will still get in. Because the extra insulation makes the roof-space colder than before in winter, the risk of dampness and condensation may increase, particularly if ventilation is limited or poor distributed.

It is essential to understand the likely effect of insulation and ventilation on the existing fabric and internal environment of the roof space, rather than to introduce additional ventilation gratuitously.

If you’ve decided to have convert the roof space into a room, a 50mm ventilation path is recommended beneath the roof finish, insulation, vapour control layer and an internal lining.

Most historic flat roofs are covered with lead, a few are clad in zinc or copper. Repairs and replacements using bitumastic (protective coating for metals) materials and felts have been widely used. Flat roofs show a wide variety of designs, although most are akin to the ‘cold roof’

Roofing Materials

Tile, stone and slate roofs used to be laid without sarking felts (An additional layer within a roof that insulates or reflects heat), although sarking boards boards were occasionally used.

Re-roofing now almost always includes underfelts to allow the work to take place in bad weather. Vapour-permeable materials are most popular. However, even these materials reduce air movement and alternative provision for ventilation may be necessary, though designed ‘breathing’ construction is now becoming possible.

Insulating foam is sometimes sprayed onto the underside of tiles and slates and sets into a hard layer. However, they are not recommended for historic buildings because jeu prevent the slates and tiles being salvaged during the next re-roofing. This is because the tiling battens and the upper parts of the rafters are sealed in, which may lead to rotting and premature degradation, because the normal flow of air into the roof space is restricted. Thatching provides one of the best natural insulators and should not need further insulation.

Taken from Energy Efficiency and Historic Buildings – English Heritage

Summer is just around the corner! If this summer is anything like last year, we’re guaranteed some hot weather and sunshine. There’s nothing worse than sitting in a boiling hot house when the weather is so great outside. Therefore, here are some design tips to consider when looking at designs for your new build to keep your house cool in the summer.

1. The use of living walls and roofs – Living walls not only shield buildings from direct sunlight, but evapotranspiration by plants also helps cool walls

2. The thermal mass of your building will also contribute to the heating and cooling of the building. During summer it absorbs heat during the day and releases it by night to cooling breezes or clear night skies, keeping the house comfortable. In winter the same thermal mass can store the heat from the sun or heaters to release it at night, helping the home stay warm.

3. Utilise cross-ventilation in your home. Cross ventilation is a natural or planned process where cold air displaces warmer air, therefore creating a light breeze. This can be achieved by opening windows at opposite ends of the house and using a fan to direct the flow of air.

4. Consider the use of porches to shade south-facing windows

5. Geo-thermal heating and cooling is another excellent way to regulate temperatures in your home with out installing air conditioning

What is BIM?

BIM stands for Building Information Modelling. It is a broad term that describes creating and managing digital information about a building. Essentially, it’s the way in which architects now design buildings.

It’s purpose is to have all the information about a project in one place, in order to allow better decisions to be made throughout the design process.

The benefits of using BIM

1. This technology takes about half the time that hand drawn designs used to take, but allows us to delve into much more detail on the plans

2. Communicating the design can be made very creative and exciting. Using Virtual Realty technology you can virtually step inside your future home!

3. Facilitating collaboration has never been easier, several individuals can edit the design and input their ideas during meetings

 

4. Human error, although inevitable, can be reduced significantly as the design can be checked and corrected much quicker than with hand drawn designs

5. It makes changes to designs much easier. For example changing the size of windows can be altered at the click of a button and the roof height altered accordingly

6. Having all of the information in one place also means that it is much easier to facilitate RFI’s when needed

7. It considers the design as a whole, for example; aesthetics, material selection, access, maintenance and construction.

8. Provides spacial awareness and retains the feel of the original design