Controlling Humidity

Forget Rising Damp.  Humans are the worst enemy of houses.  It is what we do inside them that causes damp problems. Breathing, Cooking, Showering, Gas Fires - all these produce  moisture which has to go somewhere - and it does - into the air in the house. It finds cold spots and condenses - producing the symptoms of 'rising damp and penetrating damp'. In most cases, this could be prevented with the use of humidity controlled extraction, or air exchange units.

You first need to investigate the humidity levels in your home - for that you need a thermo hygrometer which tells you not only what the humidity is, but what the dew point is - this unit is the only one that is on the market for a sensible price.  See the Amazon link in the left margin of this page - it will be the best £25 you ever spent on your home.

This page shows you how to control the atmosphere in your home and prevent dampness. You can buy some superb units that will help solve your problems.  There are two ways of doing this - dehumidifiers, and mechanical ventilation. Dehumidifiers can be rejected out of hand - they do not cure the problem, they treat symptoms. Dehumidifiers are very expensive to run and need constant attention - you have to empty them and clean filters.

Mechanical ventilation systems are many and varied.  Every situation is slightly different and depends on how the house is built, the number of rooms, source of the problem and ambient temperatures.  

We have joined forces with RHL-Direct, who design and manufacture a range of ventilation systems to cover most situations.  We have confidence in Ray Hudson, who owns and runs the company.  Ray has many years experience in his chosen field, and will only offer solutions which solve problems properly. The solutions shown below are NOT the sort of things you would buy in B&Q - these are properly designed commercial extractors and will repay your investment many times over.

How to make your bathroom dry and warm:

The Warm Fresh Air Dehumidifier for Bathrooms is a fully automated bathroom fan. It has dual actions for both intake and extraction of air.  Not only does it remove steamy air after your shower, but warms fresh external air as it draws it into the building. This unique feature is available using a single vent to the outside, that will fit on to your existing 4 inch fan vent.

The unit is completely automatic and conditions the air in your bathroom with internal humidity control, external temperature sensor, light switch timed overrun, movement detector and options including air quality control of both intake and ambient room air.

Buy the RHL warm air bathroom dehumidifier...

Humidity control for your bathroom

If the warm air unit is a wee bit too expensive for you, try the extractor only option - this is a similar unit, but without the warm air input.  It runs in trickle mode all the time, making sure that your home always has a constant air change. When humidity levels rise, it detects this and goes into turbo mode to remove the excess moisture.

Humidity controlled 'Dryvent' bathroom extraction


Budget option:

There is a second option, a little less expensive, which is a unit that only comes on when the humidity reaches a certain level.  Personally, I prefer the Dryvent unit, but if money is tight, you might like to use the Wolf unit instead:

Humidity controlled bathroom extraction

Warm air dehumidifier for your kitchen:

Kitchens are the worst source of humidity I ever come across - moisture from fridges, cooking, gas hobs, dishwashers, washing machines - all of these things cause huge amounts of moisture that finds its way into your home.  Very few kitchens have extractors that vent to an outside wall - charcoal filters in cooker hoods do nothing.  The RHL kitchen vent extracts humid air and replaces it with warm dry air - these are a MUST HAVE in your kitchen.

The RHL kitchen dehumidifier

Humidity controlled extraction for your kitchen

If a warm air unit is too expensive, you can opt to fit the RHL kitchen extractor.  These have two major benefits over anything else on the market:  

  • They have a stainless steel filter that can be washed in your dishwasher.  
  • They incorporate a data logger which is especially useful in rental properties, which records temperature, humidity and fan operation to keep a record of conditions in the room.

If the warm air unit is a wee bit too expensive for you, try the extractor only option - this is a similar unit, but without the warm air input.  It runs in trickle mode all the time, making sure that your home always has a constant air change. When humidity levels rise, it detects this and goes into turbo mode to remove the excess moisture.

The RHL Dryvent kitchen humidity controlled extractor

Budget Option:

As with the bathroom units, there is a slightly less expensive model that only runs when humidity levels are high.  I prefer the Dryvent option, but this is a budget unit that will certainly help:

Buy the RHL humidity controlled extractor

Damp and Condensation
Whole House Dehumidifier

The home warm air dehumidifier system is fitted within your attic space where the air is filtered and then pre-warmed before flowing into your home through a grille located on your ceiling, this is generally in the landing area.

The dry air input runs continuously purging your property of damp and stale air . The fresh replacement air provides for a healthier living environment and when coupled with our vapour vents provide ventilation based condensation control where needed. During the warmer season the in built thermostat automatically switches off the 200 watt heater within the fan.

Note that the system extracts air from the loft area - thus making sure your loft does not suffer humidity problems.  You may need to couple this with a normal intake vent into the loft, if the soffits are blocked and air can't enter the loft from outside.

Buy the Whole House dehumidifier

At last you can monitor the humidity in your home:

These are great little gadgets - inexpensive and easy to move around your home so you can monitor humidity in different rooms.   

Dont just buy any old cheap version - this is about the only one we can find that that also displays the Dew Point - that temperature at which condensation will form given the ambient conditions in the room.  Press the mode button to get the dew point.  Remember - you need to keep humidity between 50 and 55%RH, any higher and you have a potential problem...

Every house should have one of these..


Measuring the surface temperature of your walls:

This handy piece of kit will show you the temperature of walls and other surfaces so you can see if they are at, or below, dew point.  If so, you'll be getting condensation, even if you cant see it!

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