Tue, 19 May 2026 13:37:41 +0100 https://www.greenbuildingforum.co.uk/newforum/ Lussumo Vanilla 1.0.3 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1545&Focus=22840#Comment_22840 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1545&Focus=22840#Comment_22840 Wed, 04 Jun 2008 17:55:45 +0100 SimonG
As understand it you have piping into filtration tank from your downpipe which then goes into the main tank. This tank has a pump to send water up to a secondary tank in the loft which is then connected to your system. Is that about right? I would want mine feeding the washing machine, dishwasher and toilets. Is that possible to implement easyly? What if the main tank becomes full? How do you get mains water into the system if you havent got enough stored?

If I could put in a system for under a grand I think I would. Any help would be appreciated.

(apologies for all the questions)]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1545&Focus=22872#Comment_22872 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1545&Focus=22872#Comment_22872 Thu, 05 Jun 2008 09:45:35 +0100 agu
http://www.aqua-lity.co.uk/en/]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1545&Focus=26615#Comment_26615 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1545&Focus=26615#Comment_26615 Fri, 11 Jul 2008 00:38:13 +0100 mike7 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1545&Focus=26659#Comment_26659 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1545&Focus=26659#Comment_26659 Fri, 11 Jul 2008 09:40:50 +0100 pahuk I have come across many differing arguments, most of which are represented here but have not formed an opinion as I don't think all the facts and studies have been conclusive enough to take into account all the factors and reasons for having a harvesting system.

My basic understanding of the principle reasons people ask me to specify a rainwater harvesting system are as follows;

1. help save the environment (very vague but by far and away the most common even if they don't know how it does it)
2. reduce my water usage and water bills
3. reduce the rainwater run off during storms
4. help reduce energy usage
5. help the supply of water due to restricted or no mains supply

My understanding of the arguments that have been put to me to cover each of these points (although I am not going to give any definative answers and try to present the points as I have heard them no matter how right or wrong I think they are) are as follows;

1. help save the environment.
This is a common perception among most end users (house holders etc) but many have no idea about the issues involved and why rainwater harvesting could help the worsening environmental situations but see that rain is falling on their house and they are not using it.
Saving energy is a common reason given by end users when asked how rain water harvesting helps. but I will come back to that in no. 4

2. reduce water usage and water bills.
rainwater harvesting appears to make sense in this argument as we all use water but not all of what we use needs to come from the mains.
However, the main issues that I see hear are;
a) saving water at point of use is very effective and should be employed before any other water system is considered (or so I am told) as using less water is the best way to reduce your water usage (sound simple doesn't it)
b) the costs of storing and pumping water on site may not necessarily be less than the use of mains supply after all the costs are included (not sure about this at all as it is a very hot topic and every case is different).
c) where the population is quite high and sources of water are low (i.e. the south east of england) rainwater harvesting can reduce demands on mains supply, (really don't know either way as how do water supply companies get their water and if we all capture it before they do doesn't their supply dry up?)

3. Reducing Rainwater Run Off during storms
A common one asked for by local government and environment agencies as attenuation but only rainwater harvesting where the rainwater is re-used for another purpose.
I can follow the argument that when their is a big down poor, having somewhere extra for it to go can reduce the flow of the site but if the water is being stored for re-use, once it is full it makes no impact? I suppose when water is scarce all these tanks would be low but wouldn't the ground be dry and ready for water anyway?
When discussing sustainable drainage systems with other people, I have been told to think of the aim as trying to make the site like their wasn't any hard surfaces there and let the ground do what it did before we chose to build there and on this argument, rainwater harvesting is of no assistance.
I don't know how sound this is but it seems to make some sence.

4. reduce energy usage
I have been told the idea behind this one is that water takes energy to collect, treat and deliver for use and by storing rainwater at point of use savings can be made on a number of levels.
a) transport to the point of use but their is still usually a pump to deliver the water from tank to house (gravity systems excepted) and the efficiencies of scale may cancel this out, I don't know, I don't have any figures.
b) mains water is treated and this takes energy but where it is used in the home it does not always need to be treated, using untreated water for tasks like flushing the loo seems to make sense but their are also health issues about storing untreated water to consider, use on less sensitive tasks like watering the garden is well accepted but usually dealt with by a simple rainwater butt, as I understand it, use for body washing and drinking is prohibited in the UK but please correct me if I am wrong.

5. help the supply of water due to restricted or no mains supply
This is where the situation is key as if you don't have access to a limitless or plentiful supply of water (mains water is not generally considered limitless but can be plentiful in some areas and at some times of the year), then making use of every drop you have makes sense.
However, I do think that looking very closely at how you use water is important and should not be sacrificed as in item 2.

Although I have some reservations and can see some misconceptions in how the general public percieve rainwater harvesting, Overall I think that it is a good idea as we have been doing it for a very long time (remember the big dams and lakes around large country houses like Blenheim) but the reasons for using it affect the type of system used and it should not be relied upon as a sole solution to a problem, nor should water saving be neglected because of it.

This is of course only my vague and not entirely resolved opinion, I am no expert and this is no substitute for professional advice. I would be interested in other people point of view and experiences though.

Ultimately it is down to the user to make their own decisions and judge their own motivations, (please read my thread on Facts and opinions in the forum and community area)]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1545&Focus=56161#Comment_56161 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1545&Focus=56161#Comment_56161 Thu, 18 Jun 2009 14:22:18 +0100 wastetech https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1545&Focus=56174#Comment_56174 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1545&Focus=56174#Comment_56174 Thu, 18 Jun 2009 18:46:05 +0100 joe90
I plan to heat rain water for hot taps/shower around the house (precautions for Legionella required, see previous threads) and only have mains water for drinking and backup in case of drought.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1545&Focus=56175#Comment_56175 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1545&Focus=56175#Comment_56175 Thu, 18 Jun 2009 19:09:42 +0100 tony https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1545&Focus=56576#Comment_56576 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1545&Focus=56576#Comment_56576 Thu, 25 Jun 2009 11:07:57 +0100 tomaspain https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1545&Focus=56581#Comment_56581 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1545&Focus=56581#Comment_56581 Thu, 25 Jun 2009 12:07:45 +0100 Julian



On a positive note - I'm not sure that's right joe90 - we have used washing machine and dishwasher on gravity fed system for years. It takes a little longer to fill than mains but works perfectly well.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1545&Focus=56704#Comment_56704 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1545&Focus=56704#Comment_56704 Fri, 26 Jun 2009 20:33:25 +0100 joe90
From another thread on this subject where people said they could not use tank fed water for machines because of pressure valves I trawled manufacturers websites for specific data on water pressure required to fill these machines and from these sites I found that between 0.5 Bar and 1 Bar was required by most manufacturers, this translates to a head of 5 metres to 10 metres, therefore I was wrong to say it would not work but should have said check the machines requirement against the head of water you have, you may be lucky!!!!]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1545&Focus=80727#Comment_80727 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1545&Focus=80727#Comment_80727 Wed, 21 Apr 2010 12:53:02 +0100 penny
We are installing a 3300ltr underground rainwater harvesting tank, at this moment. I would like to use the water for all uses, apart from drinking which will come from the rising main in the kitchen. The system is direct as we have no provision for a header tank. I understand that the pump supplied with the tank pumps at 3000ltr/min. In my naivity I assumed that we could use the water for showering, dishwasher, etc., without any treatment as I lived on Sark for a while and they do not have mains water, only rainwater and that was used for everything, including drinking after passing through a tabletop ceramic filter. My builder, however, is nervous about having untreated water for showering and dishwasher. My husband was against having the rainwater harvesting (he's an accountant and works only in £s) but I loved washing in rainwater, and I won out. However, I am unable to use much more of the budget on this bit of the project, therefore, can anyone suggest a 'cheap' method of treating the water to remove the bacteria, please? We are hoping to put the control panel for the tank on the outside of the building, which panel will be semi-recessed, and could possibly put a whole-house system for treatment adjacent to this. I e-mailed a reverse osmosis company and they have said that this method is only suitable for mains water, which was not my impression.

Regards P]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1545&Focus=80729#Comment_80729 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1545&Focus=80729#Comment_80729 Wed, 21 Apr 2010 13:17:43 +0100 Nick Parsons https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1545&Focus=80762#Comment_80762 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1545&Focus=80762#Comment_80762 Wed, 21 Apr 2010 22:51:36 +0100 joe90
You need to talk to Mike7, click on his name in previous post and get his details.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1545&Focus=80838#Comment_80838 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1545&Focus=80838#Comment_80838 Thu, 22 Apr 2010 23:01:39 +0100 penny
We are hoping to fit a uv or other type of filter so that the water is doubly safe for washing. Has anyone used a ceramic whole house filter? They seem to be a lot cheaper than uv.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1545&Focus=80840#Comment_80840 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1545&Focus=80840#Comment_80840 Fri, 23 Apr 2010 06:21:59 +0100 SteamyTea
http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1822&page=2#Item_9

But this was my question?

Does anyone know anything about ceramic water filters, really after something that could handle up to 300 litres a day.

We used to install 'sand filters' and 'DE' filters for spa baths. I never got too involved with them, but I do know that they needed 'back washing' to get the dirt out. Not sure where you could back wash to, it can smell badly (will never forget the interesting odour from the Sheffield YMCA's filter).

We also used to manufacture a UV filter, was a simple device but not sure how to calculate flow and mass rates, I am sure others can find that out. Has to be remembered that we had constant flow over them, so a bit different from a storage system.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1545&Focus=81194#Comment_81194 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1545&Focus=81194#Comment_81194 Tue, 27 Apr 2010 14:24:50 +0100 wastetech Also, visit http://www.oasis-rainharvesting.co.uk/simple_guide_to_rainwater_harvesting for some very useful info on what to look for in a system.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1545&Focus=82954#Comment_82954 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1545&Focus=82954#Comment_82954 Mon, 24 May 2010 13:15:20 +0100 Carol hunter Carol Hunter]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1545&Focus=82995#Comment_82995 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1545&Focus=82995#Comment_82995 Tue, 25 May 2010 07:07:35 +0100 contadino
I've seen several underground reinforced cement ones built around here (Italy), but the general advice is that blockwork ones aren't as long lasting as cement. The vase-shaped ones don't seem to be built at all any more.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1545&Focus=83008#Comment_83008 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1545&Focus=83008#Comment_83008 Tue, 25 May 2010 13:54:24 +0100 Gotanewlife https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1545&Focus=83011#Comment_83011 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1545&Focus=83011#Comment_83011 Tue, 25 May 2010 14:37:44 +0100 contadino
My water tank is 5.5m x 4.5m x 4.5m, square, made from re-informed cement.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1545&Focus=83013#Comment_83013 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1545&Focus=83013#Comment_83013 Tue, 25 May 2010 15:41:02 +0100 Gotanewlife