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  • Writer's pictureDavid @ Pest Control 24/7

Rats in drains and emergency pest control in Dorset.

Rats and drains – the perfect combination When we get a call out for a job involving any internal problem with rats, we start by conducting an extensive survey of the property which includes any adjoining parts of the building when it comes to rats you have to see the whole picture, so we include any properties which are attached to the one which we’ve been called for. Rats are without doubt the biggest pest in numbers that we deal with, and we carry out more rat control in Dorset than anything else and that includes all the insect pests we deal with.

Rats in Dorset When it comes to the rat treatment, we look for obvious signs, such as a bad joint where the mortar has slipped out, or a gnawed open-air brick and the ubiquitous pipe hole that was left over from when the new kitchen was installed. But there is one fact that we can’t escape from when looking at rat problems and this is that about 70% of internal rat infestations stem from a fault under the house and in the main drainage. Throwing rat poison ‘rodenticide’ at the problem in a situation like this just doesn’t solve the problem 100%, you need to strip the layers back and understand the narrative and the only way to do that is to look inside the drains.

Types of drains There are two different types of drainage system: one that connects your house and every other house in the street to the main, water companies sewer in the street outside, and the other one which only serves one property at a time and is a series of tanks that settle the solid waste from the liquid (99.9% of domestic sewerage is just water) and allow to drain away into the surrounding ground – these are termed cesspits or septic tanks and usually found on rural properties. The first system mentioned commonly has rats running around inside; they don’t actually live inside these drains as the pipes are quite narrow and there are few dry areas for them to nest in, but they do act as an easy route for rats to move around the streets of our towns and cities undetected. On the plus side for rats, as well as easy movement, these drains are full of food, and they have plenty of water. Combined with that, the ambient temperature in the drains, is about 5 degrees higher than the temperature outside, so handy in the winter.

It’s generally the drainage system that connects up to the main sewers where we find the most problems due to the scale of the system and the sheer amount of defects that occur along its length; rats will not live in these drains but faults and open manholes allow them to slip inside and from there, they will explore the system and if there are faults near, or underneath your property, then the chances are you will have a rat problem inside your home and I’ll explain why in this blog The super skills of rats To fully appreciate how problems with drains leads to infestations inside, let’s explain that rats have three major skill sets that make them our Number 1 pest in Dorset. Their first super skill is that they are resourceful scavengers and rats will sniff out every crack and cranny seeking any opportunity for food or shelter, we often find that the brickwork of older drain inspection pits where rats have spent years and years, gnawing away at an edge on the exposed bricks and squeezing through the gap created to get inside. Secondly, rats are incredibly intelligent animals, put a rat inside a maze and it’ll figure out the route through and remember it in no time at all. We have seen rats enter via the drains at one house in a series of link detached properties (these are the houses that although they are detached from one another, they all have a garage linking them between), in this case we saw rats come in and travel through the first garage, through the next house and next garage into our customer’s house. The third of our super skills goes to the fact that rats can slip through the space of a modern fifty pence piece; in today’s modern construction and the speed in which houses get built do you really think that gaps of that size are noticed? We’ll see a wide range of building defects that you wouldn’t even look twice at, which have let rats through into the interior of a building. Rats are determined, clever and highly capable so when rats are in the drainage system outside your home, it’s a given that they are working on getting inside.

Rats and drains the perfect combination Suitably equipped with a range of super skills, any defect in the drainage system is going to be exploited by these animals and you will find yourself with rats running through the loft and cavity walls and we’ll explain why this happens. When the drains enter the property, they generally pass through the outside wall, in effect they punch through underground and you have a point of access alongside the pipe as it passes through the cavity wall, this entrance leads up the inside of the walls and into the loft. One-way valves or RATWALLS The best way for preventing rats accessing your property via the drains is by installing RATWALLS – selling one way valves as a ‘cure’ for a drain with a defect, these valves can be either metal or plastic and the idea is that they are inserted into the outlet of the faulty section and act to prevent the passage of rats going against a hinged flap. Plastic valves? We’ve already said that plastic is no deterrent against the teeth of rats so why anyone would buy and fit a plastic valve is beyond me but they’re for sale on the internet at all sorts of prices, the metal ones work, they have proven them self’s time and time again and in marine grade steel they do not rust. Any drain repair is going to be expensive and generally when it includes a survey, the cost is around £1000 and upwards, we’ve seen repairs which stretch into tens of thousands but this was a main sewer that had collapsed under an extension of a house in north Dorset. RATWALL drain valves are fantastic at a cost of £170.00 supplied and installed which can be stop any future infestations after the initial rodenticide treatment. remember that one day you may sell the property and not notifying the new buyer of a major fault with the drains may have repercussions! Here at Pest Control 24-7 we can carry out your drain surveys – our goal is to deliver the best possible service that we can. The drain surveys that we carryout are all part of our determination to get you rat free and the photos on this blog are just a couple of examples of how rats can damage the drain walls and gain access to your property.

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