Why fit matters more than the brand

An interceptor is a small dish that sits under a furniture leg. However, it only works if the leg stands inside it. If the foot is too wide, the dish cannot sit flat, and the bed may rock. If the foot is too narrow, it may slip about and touch the rim.

A poor fit also leaves gaps. Bugs can use a gap, so the trap stops being a barrier and becomes decoration. Our guide to bed bug interceptors explains how the two wells work. This post covers the step before that, which is checking that the dishes will fit at all.

What to measure on each leg

First, look at the bottom of the foot, because that is the part that touches the dish. Use a tape measure or a ruler, and write each figure down. Also note the shape, since a square foot is wider across its corners than across its sides.

Next, measure these points on every leg:

  • the width of the foot at its widest point
  • the height of the foot’s flat end above the floor, if the leg has a rounded or tapered end
  • the distance between the leg and any nearby bed rail, drawer or panel

Then check that all legs match. Many beds have a thicker centre leg, or a different foot at the head end. As a result, one box of identical dishes may fit three legs and not the fourth.

Finally, read the product listing or the manufacturer’s instructions. Check whether they state the largest foot the dish will take. Compare that figure to your own measurements, and leave a little spare room.

Casters, castors and wheels

Many beds sit on wheels, and that changes the sums. A caster is wider than the leg above it, and it often swivels. Measure the wheel and the plate it turns on, and measure how far it sweeps when it turns.

If the wheel fits inside the dish, you may be able to lock it and place the dish under it. However, a swivelling wheel can climb out of a shallow well when you push the bed. Lock every wheel first, and check the bed does not slide.

Divan bases and solid frames

A divan has a solid base, and its feet are often short and wide. Some have no feet at all, so the base rests on the floor. As a result, a leg dish has nothing to sit under.

To check, tip the base up carefully with a helper and look underneath. Then measure each foot and the gap between the base and the floor. If the base sits flat, you cannot isolate it with dishes, so a different monitoring method may suit you better. Our guide to sticky traps and where they help covers one option.

When the feet do not fit

Some furniture simply will not work with standard dishes. Here are the choices, from simplest to hardest.

First, look for a larger dish made for wide feet or wheels. Some sellers list a maximum foot width, so check before you compare options in our round-up of bed bug traps. Next, think about whether the bed can be raised. Do this only with proper risers made for your frame, because a stack of blocks is not safe to sleep on.

If neither works, treat the interceptor as a partial tool and add another. Lure-based monitors and how they work are one example, and they can sit beside the bed rather than under it. Whatever you pick, remember that what traps can and cannot do is limited. A monitor tells you about activity near it, and it does not prove a room is clear.

Keeping a raised bed safe

A dish adds a little height under each leg. Because of that, the small lift changes how the bed sits, so check the stability before you trust it.

First, press down on each corner. Then rock the frame gently from side to side. If it wobbles, level the feet or choose a dish with a wider, flatter base. In addition, never use a dish under a leg that carries a heavy load unless the maker says it can take the weight. Keep bunk beds, children’s beds and any bed with a person who has reduced mobility to the manufacturer’s guidance, and do not improvise.

Also think about getting in and out of bed. For example, a higher mattress can be harder for children and older people to climb onto, so test it yourself first.

Set up the bed once the dishes fit

Fit is only the first step. Pull the bed a short way from the wall, and keep bedding off the floor. University extension guidance says interceptors help only when the furniture cannot be reached by another route, such as a wall, a curtain or trailing bedding.

Our step-by-step guide to using bed bug traps covers the routine, and it explains how often to check. If you meet a bug while you check, bed bugs after travel may explain how it arrived. Likewise, if the bed came from elsewhere, second-hand furniture checks help you plan what to look for.

When to call in help

The NHS says it is very hard to get rid of bed bugs yourself, and it advises contacting your local council or a pest control service. So if you find live bugs, do not rely on dishes alone. A professional bed bug inspection in the UK will confirm the problem and show where the bugs are hiding.

Your professional may suggest a treatment, so it helps to know the difference between heat and chemical bed bug treatment. Afterwards, monitoring after bed bug treatment explains how dishes can keep watch. Keep them fitted until your professional says you can stop.

Sources

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