Cast iron gutters (rhones)

Half-round gutters, originally made of cast iron, are often found on the backs of stone tenements and are also widely used on more modern buildings.

half gutter new crop jg.jpg
A new half-round gutterJohnGilbertA new half-round gutter being tested with water. Cast iron gutters come in certain radii, as well as straight lengths.

Cast iron gutters have a long lifespan, especially if regularly painted. They are made from lengths bolted together and sealed with a mastic compound.  

Problems

Choked gutters, due to roof debris and plant growth, may need to be cleaned more than once a year in some areas.

Inadequate falls and sags - get them re-fixed and add additional fixings if required.

The joints and the fixings are the most vulnerable area of your gutters. Nuts and bolts, if not rustproof, are liable to rusting and the jointing compound can dry out. If there is a leak at a joint, it may just need to be opened up and re-bedded with new mastic and stainless steel nuts and bolts.

Repainting and repairing your gutter

  • repaint every 5 years (3 years in exposed or salty environments) - check the painter has allowed enough preparation time for proper cleaning and rust removal
  • check also for rust holes and leaks at the back of gutters where painting is tricky
  • deal with rusty fixings before they allow the gutter to fail
  • deal with inadequate falls, and areas where there are pools of standing water
  • glass fibre compound bandages are available for making temporary repairs, but when you've paid to get a worker up there, it's worth getting the joint fixed properly

Replacing gutters

  • cast iron replacements may be more expensive than alternatives such as glass fibre, plastic, and pressed aluminium, but should last a lot longer
  • cast iron also comes in a variety of shapes which are not always available in other materials
  • when replacing your gutters, get them enlarged to deal with current climate conditions

Professional help recommended?

Although the work may appear straightforward, ensure your builder or tradespeople have the skills for the job. If in any doubt, get professional help to specify and organise the repair.

Further information

Historic Scotland Inform Guide 'The Maintenance of Cast Iron Rainwater Goods'

Historic Scotland Short Guide 'Maintenance and Repair Techniques for Traditional Cast Iron'