Find a Roofer you can trust in Crewe.

How To Replace Flat Roof Felt

Also referred to as tar paper, roofing felt is installed underneath the roof’s shingles to help deny water access to your home. Installing the roofing felt in overlapping layers builds a water barrier in situations whereby the weather damages or blows away the shingles. Although the application of a roofing felt on a flat roof is relatively easier and safer than working on a peaked roof, it’s advisable to take enough care and precautions. If you lack proper training and experience for this task, we’d recommend you employ a reliable professional to guarantee the best results and save you from further headaches especially in cases whereby unfortunate errors are made. This step by step guide will give you a good insight into the flat roof felt replacement process.

• Take a measurement of the width and length of the roof.

• Calculate the square footage by multiplying the numbers.

• Multiply the square footage gotten by three (it’s advisable to install three layers of roofing felt to create a really strong weather barrier).

• Use a claw hammer to remove the existing roofing felt.

• Use utility knife to cut the new felt to fit the length of the roof.

• Place the first piece along the roof’s edge and use a hammer tacker to tack the felt in place with staples or galvanized nails and hammer.

• Put the staples or nails at every 6 inches along the side touching the roof’s edge as well as down the short sides.

• Repeat the same process for the second piece, laying it out beside the first row of felt.

• Cut a piece of felt to the appropriate length using a utility knife to begin the second layer of roofing felt, and cutting it in half, lengthwise.

• Apply construction adhesive along the first row using a trowel.

• Press the first piece for the second layer onto the adhesive. Repeat this process until the roof is covered with a second layer

• Apply construction adhesive over the second layer to install the third layer. Begin with a full piece of felt without cutting it in half.

• Overlap each piece by 2 inches until you’ve completely installed the third layer.

There are a few reasons why commercial buildings often have flat roofs. Lots of people argue that flat roofs aren’t as attractive as pitched roofs, which is why it’s uncommon to see a residential property with an entirely flat roof. Lots of commercial buildings don’t need to look attractive, so go for flat roofs because they’re cheaper.

Flat roofs tend to be less expensive than pitched roofs, especially for large, broad commercial buildings. Some commercial buildings simply couldn’t have a pitched roof because their width would mean that the roof would have to be extremely high. Flat roofs are also cost-effective for commercial buildings because it means that air conditioning and ventilation units can go on the roof, saving space in and around the building.

Commercial buildings also often have flat roofs because they don’t need the loft space that residential properties need. If there’s no need for the space, it doesn’t make sense to spend more money on a pitched roof just to keep the attic space empty. Flat roofs also give the commercial building owner the opportunity to use the space as a smoking area for employees or give access to fire escapes to upper floors.

If you’re having a commercial property build, make sure you speak to the experts about the type of roof that is suitable for you. If you’re planning on having air conditioning or ventilation systems installed within the property, you might be best off with a flat roof – but if you need some extra storage space, a pitched roof might work best for you.

It can be easy to repair a felt flat roof depending on the problem. If you’ve got an old-style pour-and-roll felt flat roof, you might be starting to run into problems, but even if you have a newer torch-on felt roof, issues can occur. You might find cracks, lifting, leaking flashings or dips and hollows in the felt. Luckily, there are some easy fixes – but the best thing to do to prolong the life of your felt flat roof is to get a professional to look at it.

If your felt flat roof only needs a small repair, you might be able to get away with using a paint-on fix from a tin that you just brush on. However, if you want a more permanent fix, you’ll need a few more tools and supplies.

You can use a patch of torched-on roofing felt over the crack or leak, but if your flat roof is very damaged or wet it might not take it. You can also buy liquid systems for felt roofs, but again, there is a possibility that your roof might not take it. Also most of the high-quality liquid systems are only available for trade customers, so you might be better off asking a roofing pro to do it for you.

The feasibility of this will depend on the roof’s strength, in particular its load bearing capabilities. This is simply because tiles are heavier than the metal sheeting. Normally a tiled roof will need to take a load capacity of 60kg per square metre. You will need a trusted roofing company to advise on this.

Do You Need Felt Under Roof Tiles?

Before now, roofing felt were mainly incorporated to serve as a temporary waterproof roof on a building which would later on be changed for the permanent solid tiles or slate roof. This is due to the fact that rebuilding a roof can be time consuming taking a few number of days, the roofing felt would be used to protect the structure as well as the property it contains by acting as a barrier between the house and the harsh elements such as rain, wind, snow, sleet and more, while also providing minimal insulation until the structure is complete.

However those are in the olden days, in recent times, roofing felt ( also referred to as breathable roofing membrane or breathable felt) is now being used to create a safe and waterproof roof which is long lasting and will protect your house, properties as well as other outbuildings for a long period of time while also complying with the Building Regulations. So to answer the question - yes, you’re going to need felt under roof tiles as it has been made mandatory by building regulations.

Now let’s take a look at the different functions served by felt.

✓ You’ll need felt under roof tiles to prevent the roof space from being exposed.

✓ Roofing felt protects homes where a roof has not yet been installed to serve as a temporary protective layer against the elements.

✓ Roofing felt is particularly crucial for modern homes which are constructed to be more energy efficient and work to hold warm air from escaping the house. This is great to reduce your heating bills while also keeping both you and your loved ones cosy all throughout the year.

✓ Overall, building regulations imply that an underlay underneath the slate or tiles is now a compulsory requirement.

A roof is one of the most significant portions of any property and they’re also the single part of a structure most vulnerable to impairment from the elements. If your roof suffers substantial damage over time, maintenances and re-roofing charges can be expensive, time-consuming, and stressful which is why it is imperative to keep your roof in sound structural and aesthetic order.

If a tile has fallen off from the top of your roof – you can expect to pay around £70-£100 to replace it including a different tile fitted in its place. Replacing a hip roof will cost between £4,250 and £7,250, the cost varies if you have a single valley or a double valley on your roof. For a new gable roof, you should expect to pay around £3,250 to £5,250.

What does it cost to replace my roof?

The charge of substituting your roof for a new one will be subject to the age and condition that it’s in, but usually, the cost of a new roof on an average property is around £5,500.

Some of the key factors to keep in mind when calculating the cost of re-roofing your house include:

• size of your roof

• type and size of the materials used

• shape and style of the roof

• If structural changes are required or not

• the roofing company hired

Tiled roof repair costs

If you are trying to prevent water from leaking inside your house for one or two tiles, then you can expect to pay between £100 to £200 to fix them and seal the leaks.

Flat roof repair costs

Minor jobs such as repairing flat roofs as well as sheds and garages or mending blisters can usually cost around £300.

Roofing job Price range

Replacing six ridge tiles £135-£260

Replacing six broken or missing tiles £55-£105

Cleanout of your gutter £35-£80

Replacing one right tile on rooftop £70-£100

The cost of a full re-roofing job can amount to around £3,250 to £7,250 depending on the size of your property.

Hip roof Cost range Length of time

Semi-detached home £4,250-£4,750 3-4 days

Detached home £5,250-£5,750 4-5 days

2 valleys – semi-detached home £5,750-£6,250 5-6 days

2-valleys detached home £6,750-£7,250 6-7 days

Gable roof Cost range Length of time

Standard £3,250-£3,750 2-3 days

2-valley £4,750-£5,250 4-5 days

It’s relatively simple to remove a Velux window, whether it’s Velux-branded or is another brand of roof window. Here is a breakdown of the steps you’ll need to take to remove a roof window:

1. Remove the sash (opening part) from the roof window frame. Usually there are screws in the hinges to loosen or a button to press and lift out.
2. Next, remove the tiles or slates from around the window frame along with the flashing.
3. Unscrew all the brackets around the window frame and lift out the frame.

It’s that simple! You can do all of this from inside your home – there's no need to climb on the roof. Removing the glass pane from a Velux window, for example if it has blown, is a more difficult job and should be left to a professional. It involves removing the sash from the roof window frame and then removing the surrounding parts of the sash to lift out the sealed unit. They will then place the new glazed unit into the sash frame before securing all the parts back onto the sash and fitting it back into the roof window frame.