Replacing Guttering

When a roof is being repaired and scaffolding is up it makes sense to consider repairing or replacing the guttering as well.

How much will it cost to replace guttering? Well that depends on:

• Material the guttering is made of
• Type of guttering
• Ease of access for working on the guttering
• Size of the house.

Guttering Materials

There are a number of different materials that can be used for guttering:

• uPVC: popular as low cost and easy to install. However also has shortest life span
• Cast iron: historically used but can be expensive and heavy to handle
• Aluminium: slightly lower cost than cast iron but lighter weight and with powder coated colour options. Popular for commercial buildings
• Steel: lower cost than cast iron and aluminium and available in galvanised and black finishes

Traditionally cast iron was used for gutters and downpipes but uPVC is most popular now due to the cost and reduced maintenance. As an example, uPVC guttering is around £2 per metre whilst cast iron guttering can be £20+ per metre. Cast iron is sold in 6ft (1.83m) lengths as anything longer would be too heavy to handle, whereas uPVC is available in 4m lengths. Cast iron can look highly attractive but it needs painting periodically to ensure that it does not corrode. Aluminium and steel guttering tends to be used for commercial rather than domestic buildings.

Guttering types

There are four popular designs of  guttering:

• Half round
• Deep flow
• Square
• Ogee

Exact dimensions vary by manufacturer so when replacing part of the gutter  it is always best to replace like with like to avoid leaks.

Where guttering is shared, eg on terraced houses, then mixing different types or materials can cause problems. Adaptors are available for some types and some materials eg to join square uPVC to half round cast iron.

As well as different visual appearance of different guttering types each type has a different capacity for collecting water. As a comparison, Marley quote the roof area that a straight section of guttering can cover from one downpipe, with the outlet at one end of the guttering:

• Half round: 43 sq m
• Square: 70 sq m
• Deep Flow: 90 sq m
• Ogee: 103 sq m

Depending on the size of roof and the rainfall intensity in the local area you might choose a higher capacity guttering or increase the number of downpipes.

Ease Of Access To Replace Guttering

A ladder is usually used for replacing guttering although if scaffolding is already in position it can reduce the time taken to remove the existing guttering and replace with new, particularly when heavy cast iron guttering is being replaced. See Safe Working On A Roof for guidance on safe working at height.

Where ladder access is not possible, such as where a full width conservatory has been added to the rear of a terraced house, then scaffolding may be required which will add to the cost. Bridging a conservatory with scaffolding can cost in the region of £400-£500. It may be possible to gain ladder access by removing the glass roof of the conservatory but this does need expert skills.

House Sizes

There are many different designs of house but the table above shows some of the basic house types and their sizes (note for roof area and guttering length the average bungalow will be around the same as a detached house). In simple terms it is going to cost 3-4 times as much to replace guttering on a detached house compared to a small terraced house.

Typical Costs – Cost of  replacing guttering and downpipes with uPVC:

• Terraced house: around £250-£270 to replace 7m of uPVC guttering (front and back) and 1 downpipe with adaptors to fit into rest of terrace.
  • Materials £40-£60 (depends on how guttering is attached to other houses in terrace)
  • Labour  £210 to include disposal of old guttering and making good
• Semi-detached house: around £520 to replace 21m of uPVC guttering and 2 downpipes.
  • Materials: £100
  • Labour:  £420 to include disposal of old guttering and making good
• Detached house: around £830 to replace 35m of uPVC guttering and 4 downpipes
  • Materials: £200
  • Labour:  £630 to include disposal of old guttering and making good

Note: removing cast iron guttering  is a two man job as the weight of each section can be upwards of 10kg.

Typical Costs – Cost of replacing guttering and downpipes with cast iron:

• Terraced house: around £925 to replace 7m of cast iron guttering (front and back) and 1 downpipe with adaptors to fit into rest of terrace.
  • Materials £600
  • Labour  £325 to include disposal of old guttering and making good
• Semi-detached house: around £2,000 to replace 21m of cast iron guttering and 2 downpipes.
  • Materials: £1,400
  • Labour:  £630 to include disposal of old guttering and making good
• Detached house: around £3,500 to replace 35m of cast iron guttering and 4 downpipes
  • Materials: £2,500
  • Labour:  £945 to include disposal of old guttering and making good

Note: It may be better to get parts of the cast iron downpipe replaced and the rest refurbished and repainted. A specialist firm will be able to give a more accurate quote.

Costs of aluminium and steel guttering will be lower than for cast iron but prices will vary according to the finish required. These are generally used on commercial buildings.