This piece of guttering was only just hanging on.
Imagine if it had dropped on someone's head.

Here’s the ‘executive summary' of the detailed process below.
  1. Clean off all flaky gubbins*. (*Technical term.)
  2. Glue the pieces of cast iron together using Repair Care resins.
  3. Paint your guttering. 
  4. Stand back with a cup of tea and gaze in awe at your repair. 

If you really want to know the ins and outs, brew yourself your favourite beverage, sneak a couple of ginger nuts out of the biscuit tin (not a euphemism), and read on.

Stratford upon Avon

Last year I was working for some lovely folk in Stratford upon Avon, redecorating the exterior of their house. There were some relatively new wooden windows which were easy to deal with, but at the front especially there was quite a lot of old timber which had started to rot. 

Timber repair specialist

One of my specialties is doing very durable repairs to exterior timber - that’s another blog post, or ten. But this time I noticed some broken cast iron guttering. Now cast iron is a tricky thing to repair, but as one of the first three Advanced Contractors for Repair Care Timber Repairs in the UK, I knew that their epoxy resin repair system would be just the ticket. 

I’ve lost count of the windows, frames, doors and beams I’ve repaired with Repair Care resins, but I’ve used many thousands of pounds worth of their products, so I’m comfortable with how they behave and I know exactly how they work. 

Scaffolding and the reason for proper preparation

The first step was to remove the guttering so I could give it a good clean, ready to repair. I insist on using scaffolding when working on exteriors - you really can’t do proper preparation off a ladder. Many decorators in the past just used ladders, and that’s one reason why sometimes difficult things - like really proper preparation of cast iron gutters - hasn’t been done for decades. I can usually tell when a decorator has just applied gloss over gloss, with little or no preparation and no undercoat. This just doesn’t work. It’ll eventually peel, and it’ll definitely peel once you start sanding it. Good primers, undercoats and specialist professional metal paints are designed to stick. If you're using regular interior or exterior gloss paint, it will only stick to a proper primer or undercoat, or if you're applying a second coat you can do it within a few days (before it has totally cured, and becomes slick and hard). You cannot just apply gloss paint to old gloss paint - it'll peel eventually, and it'll be a real bugger to sand next time you decorate. I could rant on.... 

Suffice to say, these gutters hadn’t been cleaned out for decades, and they’d been glossed over gloss - so when I sanded I got multiple laminates of gloss peeling off gloss - a right bugger! One of my mantras is that if you do something right, it’ll be easier to do next time. So do the preparation right, do the painting right, use the best products - and not only will everything last longer, but it'll be easier to maintain and redecorate the next time. 

Hello guttering, need a bit of Charles Budd love and attention?

The Process 

I’ll get off my hobby horse now and get on with the process - which I guess is what you’re interested in if you clicked on this blog. Unless you’re an insomniac.

1. Remove all gubbins (dirt, flaking paint and rust) from the cast iron. It’s useful to have a range of tools - scrapers, wire brushes, different grades of abrasives (‘sandpaper’ (not sand, it’s usually particles of aluminium oxide) or whatever abrasives you use). The ironwork doesn’t have to be totally cleaned back to bare metal, but take off anything flaky. 

Gubbins removal.
Note a broken tile on the left of the photo. I fixed that too.

2. Clean the guttering. You can use a degreaser if you like - there are too many DIY and professional products to choose - but Fluxaf, Virosol and EcoSolutions products all do the job. What I do is usually do a final clean with meths. It degreases well and evaporates quickly. 

3. Now comes the Repair Care resin process. It’s a process that’s been carefully developed as a very long-lasting timber repair solution, but it also works well for cast iron, and small concrete repairs. It’s based on liquid and gel epoxy resins. Different versions dry in 1, 3, 4 and 16 hours. The quicker drying the more expensive the resins are (and the more they smell!) I tend to use the 4 hour resins, as you can apply them in the morning and they’ll be solid by late afternoon.

Repair Care Dry Fix 4 (two part liquid epoxy resin)
and Dry Flex 4 (two part stiff gel epoxy resin)
This is lovely stuff - I use a lot of it.

4. The first stage is to mix and apply a small amount of Repair Care Dry Fix. This is a liquid version of the resin, and it fills air holes and crevices to create a stronger bond. Some might say you only need to use it with timber, but I’m a ‘belt and braces’ man and if there’s only just a slight advantage to using it, I’ll use it. When I do a repair, I want it to last for as long as possible. Once applied, leave it to dry a little - usually 20 to 30 minutes - perfect to have a cuppa and a couple of biccies. (Please note, you need to use either the Universal Dry Fix or the matching Dry Fix Liquid to the Dry Flex Paste - i.e. Dry Fix 1 for Dry Flex 1, Dry Fix 4 for Dry Flex 4 - ask your supplier if you need more information on this).

My customer kept me very well supplied with tea, coffee and the best biccies available!

5. Then mix up the Repair Care Dry Flex. This is a gel version of the resin. It is fairly stiff, and easy to work with - a little bit like sticky clay. ‘Butter it’ onto both sides of the repair, then push the pieces together, applying more paste if needed. Then carefully remove excess paste - you do this not just to save money (the resin is expensive, but it’s so good that it’s good value) but also because it’s very difficult to sand - even if you have high end commercial sanders like the Festool range, which I do. 

The Dry Flex resin is stiff enough to hold the pieces together in this case. 
Sometimes you need to support pieces until it has set.

6. You can clamp the pieces together, or just rest them together so they don’t move. You don’t have to apply pressure to the two pieces like with some glues - just keep everything together and still while the resin dries. 

Most people would use silicone or a similar sealant to fix this end cap back on.
by using the Dry Flex resin, I can guarantee it won't drop off, and it's totally waterproof.

7. Once the resin is dry, use a sharp blade to carve off any excess resin, and sand as smooth as needed. On old cast iron you usually won’t want to spend too long doing this, as it’ll probably be fairly pitted and lumpy anyway, and it’s just a waste of time and looks odd to have a perfectly smooth repair on a fairly lumpy bit of old cast iron! And remember, time is money, or an opportunity to have a biscuit.   

8. Apply your paints of choice. In this case I used Coo-var Hammercote. It’s a bit like Hammerite but I think it’s nicer to apply. You could use a good rust inhibiting primer (like Rustoleum Rust Inhibiting Primer - which is superb) and then your choice of any top coat, such as an exterior gloss or satin paint. The advantage of Hammercote and Hammerite is that they can be applied over bare metal without the need for a primer. 

Guttering and downpipe fixed and painted.
The boundary of the property was the downpipe,
but I painted the neighbour's bit of that horizontal piece too.

9. I’d always recommend applying at least two top coats of paint for durability and also colour coverage. 

End piece reinstalled with resin.
Guttering double topcoated inside and out for durability.

10. Once the pieces are dry, reinstall them carefully and stand back with a cup of tea and a few biccies (there’s a theme developing here) and revel in the shimmering warmth of your own achievement. 

The broken piece of guttering, reinstalled, double topcoated.
You can see I didn't strip all the old paint off, just the flaky stuff.
You can strip them completely - but that would have cost the customer more.
You can see part of the woodwork, in a satin finish. It did look like this... but that's another blog.

Anyhow, the finished front of the house looked like this. The windows were PVC, but a lot of the black woodwork had serious rot issues. All the rot removed and new timber installed with resin. I'd better get writing that blog! 


Bonus photo! 

When I started this blog, I'd completely forgotten that there was a broken tile on the roof. Now it's usually cheaper to replace tiles, but in this case I'd have had to source a tile, then replace it. As I was already up on the edge of the roof on the scaffolding, and already mixing up Repair Care resin, I used the same process as I used on the guttering to repair the tile. It worked a dream, and the repair was invisible from the ground. Although Repair Care resins are designed for exterior timber repair, they are very adaptable to many repairs, both inside and outside the home.

PS In case you're wondering, I'm not paid by Repair Care. I've just used their products for a long time, and they are the best on the market for long-lasting exterior timber repairs, so that's why I use them and love them!