Sprinklers

[LSB]

My planning says that we must have a sprinkler system because of the distance from our nearest fire hydrant and because a fire engine would not be able to access the house due to the driveway and the restrictions placed on that.

 

Please can someone explain to me how they work, in simple terms, how do they get the water, how do they know when to run, are they all linked so if the one in the snug goes off will the one in the master bedroom 20m away also go off.

Do they need electricity.

 

Do they ever fail, we will have a wood burning stove and sometimes the smoke 'leaks', will that set it off.

 

If they go off, will insurance cover any damage done, assuming it is an accident and not a fire, which is obviously covered.

 

TIA

Jill

 

 

[Ferdinand]

1 hour ago, LSB said:

My planning says that we must have a sprinkler system because of the distance from our nearest fire hydrant and because a fire engine would not be able to access the house due to the driveway and the restrictions placed on that.

 

Please can someone explain to me how they work, in simple terms, how do they get the water, how do they know when to run, are they all linked so if the one in the snug goes off will the one in the master bedroom 20m away also go off.

Do they need electricity.

 

Do they ever fail, we will have a wood burning stove and sometimes the smoke 'leaks', will that set it off.

 

If they go off, will insurance cover any damage done, assuming it is an accident and not a fire, which is obviously covered.

 

TIA

Jill

 

 

 

I would think it should but you would need to check the policy. But a sprinkler system will do about 95% less damage than the fire brigade, and accidental setting off is very rare.

 

One of their main selling points is that fires get restricted to a single room, and they use relatively little water.

 

Briefly, they have a separate mains supply and sometimes a tank in eg the loft, the sprinkler heads are concealed in the ceiling, and they detect a fire by having a link which melts when the air temperature reaches 60 degrees C or so and it drops down and turns on. Normally there would be a sprinkler head for every 3m x 3m area (ish). There is a separate water pipe system, and they do not need electricity.

 

They do not use  the same mechanism as smoke detectors, which usually use an optical sensor to see smoke, so are toast proof and should be woodburner proof unless it has started a fire and triggered the heat detector.

 

There are also systems which use a water mist rather than a spray. You need very few of these, but they tend to cost a lot of money for each one.

 

They are not normally linked (ie Hollywood is lying about the hero setting a fire in a waste basket to flood the entire building and kill all the zombies with 784 sprinklers going off at once).  

 

Hollywood, lying. My faith is shattered - it even happens in Spongebob Squarepants.

 

 

Edited October 1, 2020 by Ferdinand

[Mr Punter]

Cost is about £2,500-£3,000 for 4 bed house.

 

They don't activate by accident.  They are fit and forget.  There is an isolator normally near the entrance, so they can be switched off after the fire is safely extinguished.

 

Because they activate quickly and only close to the fire it can be brought under control very quickly.  If you have to wait 20 minutes for the fire brigade you may have to say goodbye to the house.

[LSB]

21 minutes ago, Mr Punter said:

Cost is about £2,500-£3,000 for 4 bed house.

 

They don't activate by accident.  They are fit and forget.  There is an isolator normally near the entrance, so they can be switched off after the fire is safely extinguished.

 

Because they activate quickly and only close to the fire it can be brought under control very quickly.  If you have to wait 20 minutes for the fire brigade you may have to say goodbye to the house.

Thanks Mr Punter

20mins, that would be remarkable here, but the biggest issue is that our new build is 120m from the road up a hill on a grass track so the appliance won't get there.

 

That's why planning are saying we must have, but it's good to hear that they work well and only in the locality of the fire and not the whole house.

 

[LSB]

2 hours ago, Ferdinand said:

 

I would think it should but you would need to check the policy. But a sprinkler system will do about 95% less damage than the fire brigade, and accidental setting off is very rare.

 

One of their main selling points is that fires get restricted to a single room, and they use relatively little water.

 

Briefly, they have a separate mains supply and sometimes a tank in eg the loft, the sprinkler heads are concealed in the ceiling, and they detect a fire by having a link which melts when the air temperature reaches 60 degrees C or so and it drops down and turns on. Normally there would be a sprinkler head for every 3m x 3m area (ish). There is a separate water pipe system, and they do not need electricity.

 

They do not use  the same mechanism as smoke detectors, which usually use an optical sensor to see smoke, so are toast proof and should be woodburner proof unless it has started a fire and triggered the heat detector.

 

There are also systems which use a water mist rather than a spray. You need very few of these, but they tend to cost a lot of money for each one.

 

They are not normally linked (ie Hollywood is lying about the hero setting a fire in a waste basket to flood the entire building and kill all the zombies with 784 sprinklers going off at once).  

 

Hollywood, lying. My faith is shattered - it even happens in Spongebob Squarepants.

 

 

Thanks Ferdinand for your explanation, most of the rooms are about 4x4 so I'm hoping that one will be enough, except the family room which is 70m2 so will need multiple.

The house is only on one level and won't have a loft so we will need to find a different way to get pressure as there won't be a header tank.

When it was pig sties they had a huge tank outside on a brink plinth to get enough water pressure.  I think we will go for pumps as that was pretty ugly.

 

[Vijay]

I'm sure someone posted that there's a yearly check that's required too?

 

[LSB]

9 minutes ago, Vijay said:

I'm sure someone posted that there's a yearly check that's required too?

 

thanks, I shall investigate this as well.
we want to self install if we can and just have it certified.

[Gus Potter]

Good points from all, ta. Just a thought. It's worth at this stage having a look at the size of the tank you'll need.. water is heavy. Look ahead and see if this will impact on the structure, would look a bit odd on the roof but you could make a feature of it, if so what are the possible cost implications.

 

If you are on a hill then you may be able to sit the tank above the house in the garden if you have enough slope and gravity feed it all?

 

 

 

 

Edited October 1, 2020 by Gus Potter
Missed a bit

[Gus Potter]

You'll still need a pump to activate to get the pressure though.

[Ferdinand]

Most domestic systems just use mains pressures; you have a separate and larger pipe and the mains pressure does the job. I think you have 0.5bar and a big pipe.

 

90% of domestic fires only activate a single sprinkler.

http://www.ultrasafe.org.uk/wp-content/uploads/2013/01/Water-Protocal-Doc-V2.pdf

 

Talk to a respected local company for15 minutes, and they will give you the gen.

 

It’s really not as exotic as it may sound. Some places (Wales) fit them by law in all new builds.

 

F

 

Edited October 2, 2020 by Ferdinand

[Ferdinand]

Here are the guidelines from my water company.

https://www.stwater.co.uk/content/dam/stw/stw_buildinganddeveloping/domestic-and-residential-fire-sprinklers-design-policy-and-guidance-final-v5.pdf

[LSB]

10 hours ago, Gus Potter said:

Good points from all, ta. Just a thought. It's worth at this stage having a look at the size of the tank you'll need.. water is heavy. Look ahead and see if this will impact on the structure, would look a bit odd on the roof but you could make a feature of it, if so what are the possible cost implications.

 

If you are on a hill then you may be able to sit the tank above the house in the garden if you have enough slope and gravity feed it all?

 

 

 

 

good idea, but won't work as the house is right at the very top boundary of the site, at the top of the hill.

we really don't want a tank on the roof if we can avoid it, but it may have to go back to the old farming days and we build one on a brick plinth and then hide it somehow.

 

[LSB]

8 hours ago, Ferdinand said:

Here are the guidelines from my water company.

https://www.stwater.co.uk/content/dam/stw/stw_buildinganddeveloping/domestic-and-residential-fire-sprinklers-design-policy-and-guidance-final-v5.pdf

thanks, I shall have a look over the weekend

 

[Mr Punter]

14 hours ago, Vijay said:

I'm sure someone posted that there's a yearly check that's required too?

 

 

It is advisory, not mandatory.  They mainly check that the sprinkler heads have not been sealed with paint and mastic and they do a flow test at the intake.  If you have a pumped systems it is probably worth doing but not for a main pressure system in a private dwelling.

[Tony C]

Hi,  I have gone through the same situation.

My house is more than 45m from the street access, not the whole house but a living room and a bedroom are out of reach.

This system called Automist was chosen - the wall mounted censor splay the Mist towards fire -  using much less water and causing less damage to the house/furniture etc.

https://plumis.co.uk/

Depends on the area of coverage, this system could be same price as the normal sprinkler. If you are installing to whole house then it might work out more extensive.

First of all, you will need to engage the Building control who is familiar with fire engineering. They will determine which area needs sprinkler fitted, either partially or whole house. If you like the Mist system above, it is worth speaking with them who they recommend.

 

 

 

[Mr Punter]

OP needs whole house cover.  The mist systems are good for small areas / kitchens in student HMOs but cost prohibitive for whole house.

[LSB]

1 hour ago, Tony C said:

Hi,  I have gone through the same situation.

My house is more than 45m from the street access, not the whole house but a living room and a bedroom are out of reach.

This system called Automist was chosen - the wall mounted censor splay the Mist towards fire -  using much less water and causing less damage to the house/furniture etc.

https://plumis.co.uk/

Depends on the area of coverage, this system could be same price as the normal sprinkler. If you are installing to whole house then it might work out more extensive.

First of all, you will need to engage the Building control who is familiar with fire engineering. They will determine which area needs sprinkler fitted, either partially or whole house. If you like the Mist system above, it is worth speaking with them who they recommend.

 

 

 

thanks, I will have a look

 

[LSB]

52 minutes ago, Mr Punter said:

OP needs whole house cover.  The mist systems are good for small areas / kitchens in student HMOs but cost prohibitive for whole house.

you are right, I do need whole house, sounds like you know more about this than I do.

I have 240m2 to cover.

 

[Ferdinand]

1 minute ago, LSB said:

you are right, I do need whole house, sounds like you know more about this than I do.

I have 240m2 to cover.

 

 

@Mr Punter develops niche housing projects.

 

Quite a lot of types of people on BH ? .