5 mistakes to avoid when renovating your roof

1. Bad ventilation

Ventilation for your roof structure is important to keep it dry. When not done properly, condensation can form and the moist can damage your roof structure. The water drops that form on your roof frame and sheathing can fall down and seep through your ceiling structure, causing additional damage.

A poorly vented attic might also be warm enough in winter to melt snow on the roof, while the eaves remain cold. When the meltwater reaches the eaves, it freezes and forms an ice dam, causing meltwater puddles to find their way under the shingles.

Proper roof ventilation evacuates the rising warm air near the peak of your roof, while drawing in fresh air in from the eaves. So ideally, half of the vents should be higher up, and the other half lower down. The goal is that the temperature and humidity levels in your (uninhabited) attic match the conditions outdoors.

2. Wrong choice of materials

You need to adapt the roofing materials to two factors: the supporting structure and the roof pitch. If your roof structure is weak, you cannot put a heavy roofing solution on top of it, e.g. clay or ceramic tiles. You would then have to choose a lighter material such as fibre-cement slates, or alternatively reinforce the roof structure, which generates extra renovation costs.

The pitch of a gable roof also determines the type of roofing material you can use. For steep pitches, more options are available. But for flatter slopes, you need to make sure the water does not penetrate between the tiles, slates or shingles, especially when ice or dirt might form a dam. For low pitched roofs, you better resort to full length roof panels.

Last but not least, you also need to adhere to the local building regulations. In most countries, the building authorities prescribe or limit roofing options to maintain a coherent look of the houses in the area. Check with your building authority which materials, but also which roof shapes and colours are allowed.

3. Not working with professionals

A roof renovation is costly, so you might be tempted to do it yourself to save a bit of money. But we recommend that you get professionals in, as a roof can make or break your home. If you get it wrong, a lot of damage can occur. Professional roofers also have the appropriate tools and safety equipment to renovate your roof in the best conditions.

Working with a certified professional is often also a precondition to get grants for your roof renovation, especially if you combine it with insulation to make your home more energy efficient. The grant you get pays towards the extra costs of hiring a professional, and you don’t have to worry that it is done right. In any case, professional contractors usually give you warranty on their work and the materials used.

4. Neglecting the importance of insulation

When you need a new roof, this is the perfect occasion to also add a layer of insulation under it. That way you don’t only get protection against rain and snow, but also against the cold (and heat). Ask a professional to calculate the recommended thickness of the insulation for your house. It would be sad if you do all the renovation works, without getting the best return on investment out of it.

Adding insulation under your roof requires some technical knowledge and skills. If you leave air between the insulation and your roofing, you run the risk of condensation which then can settle in your insulation material and reduce its effectiveness. Mostly, professionals would add a vapour screen under the roofing, to protect the insulation from possible moisture coming from outside.

5. Health and safety

Even though you might feel adventurous, working on a high roof is risky business. That’s why professional roofers have all the needed equipment to avoid accidents: steady scaffolding, anchoring, safety harnesses, adapted shoes, railings, safety nets… They are put in place to protect themselves, but also the people passing by the building site. You don’t want to get a tile falling on your head.

Looking for a professional roofer? Find them via Cedral world.