A chimney terminal is the bit right at the top – sometimes known as a cage, cap, cowl, birdguard or ‘chimney thingy’! There are a number of uses:
- Keeping out birds (Jackdaws) who nest in the flue and vermin such as squirrels
- Keeping out rain
- Combating down draught problems
Some homes may not need anything on the chimney – sometimes a chimney pot is sufficient – indeed occasionally even a pot isn’t needed! But anyone with a woodburner, multi-fuel stove, AGA or similar appliance are advised to have a cowl of some type, if only to prevent water ingress – water will rust away the metal box beneath and can mix with the soot to create a corrosive substance in the flue.
Having the correct terminal is important and we frequently see the wrong type fitted and/or fitted incorrectly – perhaps the wrong advice has been given or simply the customer has changed how they use the flue and not considered the other end of their chimney.
Simply put, whatever is fitted to a ‘live’ chimney (one in use) should be installed so that it:
- can be swept into without dislodging it – ensuring that the flue is clear all the way to the top
- allows the safe removal of gases caused by combustion to pass out of the flue
- prevents condensation build up in the flue of a disused chimney
If you use any appliance or open fire you should NOT have this type of terminal on your chimney. They are dangerous as fumes are prevented from escaping quickly enough – they are not designed to be used with a live flue and could result in the build-up of highly poisonous carbon monoxide.
If you have a problem with birds, rain or vermin entry into your chimney – there’s a cowl for that. The silver one on the right can also aid with a down draught (in certain circumstances). There are also a variety of chimney pots and cowls for lined chimneys.
This terminal is a no-no for any live chimney. It doesn’t prevent any birds entering – in fact it’s a lovely shelter for the birds – and the cowl will impede the outflow of fumes. In addition, the design of many clay terminals, which are not intended to get hot, means that the tops can crack and be dislodged in windy conditions or when the chimney is swept. This can damage roof tiles/slates…or worse!
If you need any ‘terminal’ advice contact your local professional qualified chimney sweep or experienced chimney expert builder or woodburner supplier. Whilst a roofer will be able to install a unit they may not have the necessary skills to advise what should be fitted for safety.
Wilkins Chimney Sweep
Around 6 weeks ago we noted that the ‘chimney birds’ were collecting twigs – and now they have begun to create more little Jackdaws.
It is a little earlier than other years but we have found eggs in nests in Newbury and Brighton already so we will be unable to remove any live nests (unless it’s a major emergency!) until the beginning of July. This is the law and we are respectful of the RSPB approach to this.
If you think you have a nest in your chimney, do get in touch because we can book you in for the earliest possible appointment once any offspring have hatched and flown. If you believe you have a nest call us – we’ll be happy to check. We can arrange to have a birdguard fitted as well to prevent any further intrusion. Jackdaws return each year to the same place to nest. By making your flue bird proof it may relocate the birds to the nearest flue so you might like to consider having additional chimneys at your property protected and to talk with your neighbours about this as well.
Bird nests in a live chimney flue may create a serious carbon monoxide hazard as there is no way for the gas to escape from the room –carbon monoxide is a killer, but a silent one, so do make sure you have a suitable CO alarm if you’re burning solid fuel or use a gas fired appliance in your home.
Bird nests are also a common cause of damp in a chimney breast – it appears to have been commonplace for people to simply block off the chimney if there was a nest in it – particularly in redundant bedroom chimneys. If you have a recurring damp problem it might be worth a call to your sweep to see if there is anything that can be done – although, as full access to the chimney is required, the fireplace will need to be unblocked before we can sweep.
The good news is that the advent of these Jackdaw babies also heralds the Spring – and it’s been a lovely one so far!
Franchise Director, Wilkins Chimney Sweep
Having written about Jackdaws throughout April, I suppose I was only marginally surprised to read this article:
What did surprise me is that having lost part of a building to a fire due to a Jackdaw nest, nobody thought to provide a decent bird guard to prevent it happening again. Even on a listed building there are ways to prevent bird ingress. The fitter may not have a complete range to hand but should be able to source something that will suit both pocket and style.
Wilkins Chimney Sweep fit from ladders where possible but I spied the scaffolding at this property – that’s the perfect time to make sure that the chimneys are protected – either capped if not in use or guarded against bird ingress with a cowl some form of wire cage.
The right cowl can also prevent rain ingress – great if you have a woodburner since these rust if rain is allowed to enter the flue.
It would be so great to hear that chimney fires are a thing of the past! Regular cleaning and protection from birds and rain will go a long way to make this happen.
Several chimney sweeps have now reported finding eggs in nests they were going to remove so we are not going to be able to remove any further Jackdaw nests until the season is done. It’s great news that it is Spring but challenging if the chimney is blocked and the weather turns cold as predicted.
We hope that our customers will understand – and we are more than happy to book in a nest for July when the nesting season should be over – but we do like to keep inside the law and comply with RSPB guidelines in this matter.