The Ratflap - anyone have any feedback on these?



Recently we had some remedial work done to fix a cracked pipe in the main drain at the front of our property. As part of the works the interceptor was removed and we are now left with a straight run out to the main sewer.

Having had issues with rats at other properties I requested there should be some form of rat prevention in this drain.

The contractor have suggested using a product called The Ratflap.

We have a 6" outflow to the main sewer, so a 6" version of this device would be placed in the entrance of that outflow pipe.

Has anyone come across this product? Anyone use is regularly? Seems like a solid solution, but can't find any real feedback on it.

Many thanks
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My feeling's too!!
Have you come across this product?

I wouldnt trust that device, with nothing physically holding it in the pipe it could all too easily dislodge and cause a blockage, or if the wire snaps, it could get washed further down the pipe and cause even more chaos. (If it couldn't be removed then excavation to remove it would be the only option. In a deep sewer in the middle of a main road, then ££££££'s! :eek: )

We'll never get rid of rats, our lifestyle and throwaway society has encouraged them to breed like wildfire. If the drains are maintained in a suitable condition, any potential exit points are blocked off, and any possible food sources are removed and/or contained properly, then the rats will go elsewhere to find an exit.
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So in you're opinion we shouldn't install any device at all? I understand the concern for this unit getting dislodged, but feel very nervous having nothing to stop the rats getting into our drainage system. Are there no products which people are happy with?

At our previous home, the interceptor was left uncovered after we have completed renovation works and despite having an entirely brand new drainage system throughout and underneath the property, rats entered via the uncovered interceptor, and then bouroughed out through a brand new manhole by eating through the concrete walls until they reached soil, then straight up into the garden. We didn't notice their entry / exit for some time and they made a hell of a mess.

Very keen to find some sort of solution.

What about this more expensive option, the RatBlocker by Vermend?
There's plenty of interceptors out there in drainage systems with the stopper missing from the rodding eye, giving rats an easy exit into the house drainage system! Like I said, we'll never get rid of them but if you block off any possible exit points and avoid providing any potential food sources then they've no reason to bother you. I do wonder if you're trying to solve a problem that doesnt exist, have you actually seen a rat? :confused:

If the drainage system is in good condition (no broken pipes or vents near the surface), they have no exit route. Rats look for light indicating they're near the surface. (For this reason toilet pan connectors or soil pipes that may allow light through the walls are banned under the Building Regs.) Once on the surface they're looking for a food source, bins, poultry/animal housing etc. My property is Victorian, street was built in 1896. Majority of drains are of the same vintage, but remain in good condition and as a result, whilst I believe there may be a rat presence in the drains, there is no evidence of any activity on the surface.

If they've eaten through concrete then that is usually a deperate measure, although as rodents, they need to constantly gnaw to keep their teeth in check, they usually go for something softer! I would suspect they had a good reason to want to exit there, either were trapped in your system or had found a food source.

I have worked with drains for many years, whilst evidence of rats is often present, and we always take suitable precautions against Leptospirosis, I have never seen a rat in a drain. (Plenty in bins behind the Chinese/Indian takeaways though!) :eek:
Thanks Hugh - good advice. You're right, I've not actually seen a rat in our system yet, but we're motivated by the previous experience and also the contractor made the recommendation too.

When you say block all exit points, can you explain further what the most common points of exit are. Our system is new, but I don't want to miss the obvious.

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Thought The Rat Flap appeared mainly in Vegas :LOL:

Occasionally known to visit these parts too:
Rats will find an exit somewhere near the surface, be it a broken pipe, or vent. A lot of older properties with interceptors had a fresh air vent fitted near the boundary, connected to the manhole nearby. Idea was, air passing over the top of the soil pipe would draw fresh air in via the lower vent, thus ventilating the house drain. (Main sewer in road was sealed off by the interceptor, and was vented sperately with a 'lamp column' type affair.) These lower vents were an early type of AAV, fitted with a mica flap to allow air in, but keep smells out. The flap breaks or disappears over time, best option if fitted is to block it off at both ends.

If the house drainage appears to be in reasonable condition then I wouldn't be overly concerned. Rats will soon make their exit evident, small pile of fresh soil where they've dug out a new entrance, with a 'rat run' leading away from it, thin tracks on the ground where they've been back and forth. They'll keep close to a fence or wall for safety, only scuttling across an open area if they really have to.

Old outside WC's are another favourite, if the WC is unused and the trap is allowed to dry out then they'll use it for an escape route!
have just fitted the 6 inch one with double flaps, has two side rails to lock it into position, works really well and fits real tight.
get the trap fixed properly,fit the rat trap as a last resort only.some give problems.
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