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    Is a PIV Unit Right for Me?

    PIV units have been installed in over a million homes in the UK, with thousands more being added by the year. At Environ, we install PIV units across London for the lowest price you’ll find in the UK.

    So why are PIV units so popular? And are they right for your property? Read my guide to find out everything you need to know about PIV units.

    How do PIV units work?

    PIV units work by creating positive air pressure in your building.

    Positive air pressure means that the air pressure inside the building is higher than it is outside, which forces air out. If the air pressure is negative – higher outside than inside – air is drawn in.

    By forcing air out the building, you cycle out old, stale, damp air without you having to open windows. Condensation is reduced to almost nothing, and your heating doesn’t have to work any harder.

    In fact, if your PIV is installed in the loft, your heating demand may be reduced. Hot air rises and usually escapes through the loft, where all this heat goes to waste. PIV units recycle this warm air, keeping a more consistent temperature in your property.

    Also, as you can reduce condensation and enjoy fresh air without having to open your windows, your heating demand is reduced even further simply through the change of living habits you will enjoy.

    Can I have a PIV unit installed if I don’t have a loft?

    Yes, while PIV units are ideally installed in the loft as the air they vent into the property isn’t as cold as air outside, PIV units can also be installed on exterior walls.

    You may not like the idea of cold air flowing into your property, but remember, if you have negative air pressure, cold air will be entering anyway – that’s what causes draughts!

    Are PIV units expensive to run?

    Many people assume that because PIV units run constantly that they must add a huge amount to your electricity bill.

    This couldn’t be further from the truth. The running cost of a PIV unit is a couple of pennies a day. And given the reduced heating demand after installing a PIV, they end up paying for themselves.

    For a higher running cost, you can install a PIV unit that is equipped with a heater and a thermostat to warm up the air before venting it into your property. These are best used in external PIV installations where air is drawn in from outside the property rather than the loft.

    Whichever PIV unit you install, running costs are nothing to worry and should never be a reason to avoid them.

    Will a PIV unit reduce my condensation?

    By far the most significant benefit of a PIV unit is the dramatic reduction of condensation in a property.

    The positive air pressure created by a PIV forces moist air out of a property through its existing vents.

    This is especially valuable in period or listed buildings which were deliberately designed to “breathe”, but have been subject to heavy handed insulation works that have sealed them up, with the nasty side effect of heavy condensation and damp.

    Beyond property damage and expensive damp repair works, there are numerous adverse health effects to living in a damp property with moisture-heavy air.

    According to the NHS, “…if you have damp and mould you’re more likely to have respiratory problems, respiratory infections, allergies or asthma. Damp and mould can also affect the immune system.”

    Any other benefits of a PIV?

    PIV units filter out dust and allergens such as pollen and dust mite feces from the air they draw in, whether it’s from the loft or outside, giving you fresh air without any of the particles that might aggravate you.

    Studies have demonstrated a significant link between air quality and the occurrence of symptoms for asthmatic people and other allergy sufferers. By installing a PIV unit, you can significantly improve your quality of life if you live with such conditions.

    Are PIV units expensive to install?

    That depends on who you get to install it.We can’t speak for other PIV installers, but our PIV supply & installation only costs from £950+VAT. That makes us the cheapest in the country, despite being in the heart of London.If you’ve bought your own PIV unit, we’re happy to install it for you. If you don’t know where to start, we’ll investigate your property and ask you about its usage so we can find you the ideal PIV unit for your needs from one of our recommended manufacturers.I’ve tried to answer all of your most frequently asked questions in this guide, but if there’s anything you want to know – or if you want to book an installation – don’t hesitate to get in touch by calling now or requesting your call back today.

    Terry Clark

    How To Treat Condensation

     

    What is condensation?

    When air with a lot of moisture comes into contact with a cold surface, the moisture solidifies into water, which is what we call condensation.

    Some temporary condensation is a normal part of most buildings and isn’t a cause for alarm, but if condensation stays on a surface for too long, it can cause damp problems and provide the ideal habitats for unsightly, smelly black mould or lead to rot and other associated damp issues.

    Worst of all, damp and mould can cause or aggravate a range of health problems. According to the NHS, “if you have damp and mould you’re more likely to have respiratory problems, respiratory infections, allergies or asthma. Damp and mould can also affect the immune system… Mould produce allergens, irritants and, sometimes, toxic substances.”

     

    What causes condensation?

    The short answer: life. Everything from cooking to drying clothes and having a shower can raise the moisture content of the air until it creates the conditions for condensation to form. Even people and pets breathing can release enough moisture to cause condensation.

    When condensation becomes a problem is when there isn’t enough ventilation for the moist air to be filtered out; if there is too much moisture entering the home; or there are surfaces that stay too cold for too long. All can lead to stubborn condensation that causes damp and mould, and if they’re all happening at once then it can rapidly make any building a deeply unpleasant place to be.

    Penetrating damp after rain? Explore damp proofing services in London.

    How to spot condensation

    A light mist on a window or a slight sheen on a wall that clears up after a few minutes is nothing to worry about, but if you see a window or a wall that is wet and dripping for hours or even constantly, then it’s time to intervene.

    You should also pay attention to the places where condensation might drip down and pool, such as windowsills. Even slight condensation can still cause problems if its forming pools of water which can cause wood or plaster to slowly rot away or grow mould.

    How to treat condensation

    The best course of action for eliminating condensation depends on the cause, which could be any combination of the following:

    • Poor ventilationThe solution may be as simple as opening windows more in the building, but if that still doesn’t create enough airflow or isn’t feasible for security reasons, then you’ll want to have simple trickle vents installed or more advanced ventilation units, which can also control air temperature to further reduce condensation.
    • Too much moistureThis likely means you have another damp problem, such as rising damp, lateral damp or penetrating damp. Click on the guides for each to learn more, as treatments can range from quick and easy jobs such as fixing a leaky gutter, to time consuming and invasive procedures like replacing plumbing or installing a damp proof course.
    • Cold surfacesThere are many reasons that a wall or window may be too cold, such as structural defects like cold bridges or cracks, or a lack of insulation in walls or single-glazed glass. If the cause isn’t obvious, heat maps can narrow down the location of the cold, helping us to find the most efficient and cost effective solution.

    If you have any questions about condensation or want to book a free, no obligation consultation and quote, call us now or request your call back today.

    Do PIV Units Work?

    Do PIV Units Work?

    Because they’re so cheap to install and run, many people have doubts about the effectiveness of PIV units.

    After all, if PIV units can improve air quality and reduce condensation, damp and mould, why do people spend so much on air conditioning? Do PIV units work?

    The short answer is yes. PIV units work, and their effect is transformational.

    We’ve installed PIV units in homes where the owners thought they would have to leave because of relentless damp problems. A few weeks after installing PIV units, and their home was given a new lease of life.

    For the long answer, keep reading.

    PIV units create air flow through positive air pressure

    To understand how a PIV unit works, first you need to understand air flow and air pressure.

    From global wind currents to chilly draughts in your house, air moves the same way: from areas of high air pressure to areas of low air pressure.

    This means that if the air pressure inside your house is lower than outside, cold air will be pulled in, while the stale, moisture-heavy air inside your house stays put.

    If the moisture in your home’s air is too high, it will collect on cold surfaces, causing condensation, damp and mould – all of which can damage your property and negatively affect your health.

    By increasing the air pressure inside your house, air will naturally be pushed outside through existing vents, along with the moisture and allergens it contains.

    This is exactly what PIV units do. By constantly ventilating your home with fresh air from your loft or outside, PIV units create positive air pressure at a fraction of the cost of an MVHR (mechanical ventilation with heat recovery) unit or full house air conditioning.

    The science is simple and the results are dramatic.

    Immediately after you switch on your PIV unit, you’ll notice an improvement in air quality and, over time, your condensation, damp and mould problems will be reduced – if not eliminated entirely.

    PIV units work in both houses and flats

    All we require to be able to install a PIV unit is a wall where we can cut out a hole between your home and an air source.

    The simplest way to install a PIV unit is to place it between the loft and the floor below. Air from the loft is pulled into the rest of the house to create positive air pressure, without any need to heat it.

    If you do not have a loft or it has been converted, PIV units can also pull in air from outside the house. However, you may need a PIV unit which heats the air so that you’re not also cooling your house in winter months.

    PIV units which heat the air have slightly higher running costs, but this is typically offset by reduced heating demand as you can enjoy fresh air in cold weather without having to open windows.

    In blocks of flats, PIV units can either be installed on an external wall or on a wall that joins to a shared stairwell or hallway. As long as you can pull air inside your home, you can install a PIV unit.

    Call us now for the cheapest PIV installation in London

    Not only are PIV units cheap to run, they’re cheap to install as well – as long as you get us to do it.We can install your PIV unit from just £950+VAT. If you need help finding the right PIV unit for your home, we’re also happy to source one for you from our trusted suppliers.Call us now or request your call back to find out more about PIV units or book your installation.

    Is Damp Coming from My Chimney?

    Leaky chimneys are a common source of penetrating damp in the roof of a property. Penetrating damp is especially dangerous in the roof due to the abundance of timber, which is at high risk of developing mould, wood-boring insects and wet and dry rot.

    While damp anywhere in a property is unpleasant, damp in a roof can lead to severe structural issues and costly repairs, such as replacing rotten timber.

    Here are some of the common causes of chimney damp and the signs to look out for.

    Damp from leaking chimney flashing

    In a typical period house, the point where the brick chimney meets the roof tiles is covered by sheets of metal called flashing, which seals any gaps between the two and stops water from pooling in the intersection of the roof and the chimney.Over time, these metal sheets can peel away from the roof or the caulk that forms a watertight seal around the sheets can become eroded. DIY attempts to fix flashing is likely to result in recurring leaks, so it’s best to leave it to a professional company who can offer a long term guarantee on the works.Leaky flashing is the most common cause of chimney leaks and dampness, the symptoms of which are usually wet, discoloured or dripping roof timbers. If the roof has been converted, you may see the plaster sagging, bubbling or forming mould from the penetrating damp.

    Damp from damaged chimney stack

    Like any other brick wall, the chimney stack is vulnerable to decayed pointing and cracked bricks, which allow water to seep inside the brick and damage them through freeze and thaw.

    Many chimneys have been repointed with concrete mortar, which damages the brickwork. Mortar should be soft and porous to allow movement in the structure and for the bricks to release moisture, otherwise you end up with wet, cracked bricks.

    You can learn more about how decayed or low quality pointing can result in damp problems here.

    A compromised chimney stack can result in roof leaks or penetrating damp. In severe cases, the structure of the chimney may be compromised, though this is very rare.

    Damp from cracked chimney flaunching

    Chimney flaunching is the mortar or concrete mix that holds the chimney pots in place. If your chimney flaunching cracks, these cracks can fill with water which widens the crack further through erosion and freeze-thaw during cold weather. If the cracks get wide enough, water can trickle down into the chimney stack or down the flues.

    Damp from damaged chimney pots or cowls

    Chimney pots and cowls are designed to stop droughts and rainwater from entering the flues if the chimney is in use. If the chimney’s unused, the pots may be capped.

    If these pots or cowls are damaged or missing, rainwater can trickle down the flues, which can lead to damp and increased moisture levels inside the property, increasing risk of condensation.

    You should have your chimney regularly inspected

    Chimneys are a part of a building that’s usually out of sight and out of mind, and in most properties it isn’t used at all. This can lead to chimneys becoming seriously decayed before anyone notices, by which point you may also have further property damage from penetrating damp.This can be an especially nasty surprise for someone who’s about to sell a property, only to find its value significantly reduced by the need for expensive chimney and/or damp repairs.It’s recommended that you have regular chimney inspections to catch any erosion, damage or leaks early on before they build up into more serious and costly problems.If you have any concerns about the health of your chimney, feel free to get in touch with us by calling now or requesting your call back today.

    How a leaking chimney causes damp issues

    • Flashing (the metal sheets which cover the intersection between the chimney and the roof) can become damaged and allow water into roof.
    • Brick chimney stacks can decay like any other wall, where damp can penetrate into worn pointing or shattered bricks.
    • Chimney flaunching is the mortar or concrete that holds your chimney pots in place. This highly exposed material can wear down and become leaky.
    • Missing or damaged chimney pots or cowls allow rainwater to trickle into the flues, which often goes unnoticed if the chimney is not in use.
    • Damp from a leaky chimney can cause severe damp and rot in your roof timbers, leading to dangerous structural issues and costly repairs.