Gutter fall accuracy

[junglejim]

I’m going to be adding gutters soon to our new build and trying to work out;

1. What the fall angle is.

2. How to align gutter accurately

3. what’s the maximum gutter run?

 

 The side of the house is approx 17m and I’d also like to connect to front gutter (9m). Ideally I’d like these to run to the back of the house down a single downpipe but not sure how doable this is. 
 

I’m thinking that the further down gutter I go the lower it will be on the fascia which over 26m could be significant and means that it’s too low. However I’m sure I’ve seen houses with very long gutter runs.

 

 Any advice appreciated.

 Thank you

Edited January 26 by junglejim

[nod]

You hardly need any fall A nail at either end and a line between them You can  use the bottom of the Facia as a guid 15 mil fall in 8 meters is fine 

17 meters is to long a run It will need splitting in half Run up to the middle Or down if you have a drain there Which is likely if your doing a new build 

[JamesP]

Agree with @nod, Last week I fitted 2 X 12 metres of Lindab to the garage.

Visually looks awkward on long runs but 2mm per metre is about right.

I tried less but left a lot of sitting water so redid the brackets.

[Russell griffiths]

You don’t actually need any fall on a gutter, if you have adequate down pipes. 
im not sure on the regs in this country or if there is any, but I find the English system totally inadequate and the thought of trying to get a run of 12m plus of gutter to go down one downpipe to be ridiculous. 
 

I stick to one outlet every 6 m which are the regs for a country with high rainfall, we will be getting lots more rain in the future as our weather patterns are changing. 
 

17m run you will need an outlet on both ends minimum. 

[junglejim]

13 minutes ago, Russell griffiths said:

You don’t actually need any fall on a gutter, if you have adequate down pipes. 
im not sure on the regs in this country or if there is any, but I find the English system totally inadequate and the thought of trying to get a run of 12m plus of gutter to go down one downpipe to be ridiculous. 
 

I stick to one outlet every 6 m which are the regs for a country with high rainfall, we will be getting lots more rain in the future as our weather patterns are changing. 
 

17m run you will need an outlet on both ends minimum. 

Thanks yes makes sense. I’m trying to figure out the surface water drainage as have soakaway in the back garden. If I drop the gutter at the front then I’ll need a drainage run to the soakaway but again seems a long way ie 25m from front of house. I’m considering aco drainage along the side if the house and wondering if it’s possible to drop the down pipe into this but again with that distance seems like it could need a lot of fall and aco could end up low. 🤔 

 

Also Would using larger guttering negate the need for multiple down pipes?

Edited January 26 by junglejim

[JamesP]

2 hours ago, junglejim said:

 Also Would using larger guttering negate the need for multiple down pipes?

We have 125mm gutters with 87mm downpipes. Have some long runs, 14m, 13m and 12m with a single downpipe for each 

and work fine so far, absolutely hammering down at the moment though. 😟

 

[Mike]

8 hours ago, junglejim said:

1. What the fall angle is.

3. what’s the maximum gutter run?

Building Regs Part H, section H3, sets out how to calculate the required gutter capacity. Your chosen gutter manufacturer will have information on the carrying capacity of their gutters when laid flat or to falls & the distance between down pipes. You need to match the two up to get your answer.

 

8 hours ago, junglejim said:

2. How to align gutter accurately

By using a string line to set out the brackets

 

Edited January 26 by Mike