What have we done...!!

[richard1976]

Hi Everyone.

Just discovered this wonderful site, and feel we will be accessing it a lot given our current circumstances!!

We have taken on a 7 bedroom house (former hotel). I understand the oldest part could be 1700s, but pretty sure most is from the last 100/150 years.

I'm a keen DIYer, but limited knowledge on the intricacies of old buildings, so will be looking for lots of guidance!
Given most of what I can see is a DIY horror show, I would imagine a lot of the unseen areas have been mismanaged in the past!

Have already put a new roof on, and central heating will follow shortly (once we establish which way to go with that!), so that pretty much blows the budget, so I will need to do whatever I can myself...


Lets start with this one...

Pics below of a crumbling wall.

This is now internal, but was at one point the outside of the back wall. Looks like repairs have been done previously, but are largely coming away. Definite dampness within the wall.

The kitchen is behind the wall to the left, so wouldnt be surprised to find similar issues there. However, this is all covered, and a new kitchen is a little further down the line.

Where should I start with this, as its freaking the other half out...! This wall will not ultimately be on display, so not worried about looks, but would like a fix that isn't going to lead to more problems down the line, and will put the wife's mind at ease...!

Many thanks

 

[paulc]

Have already put a new roof on, and central heating will follow shortly (once we establish which way to go with that!), so that pretty much blows the budget, so I will need to do whatever I can myself...

When you do the heat loss calculations for radiator sizes, base the specifications on a heat pump even if you plan on using a gas or oil fired boiler. Bigger radiators means you can run at lower flow temperatures which will equate to better efficiency - I plumbed in a new heating system here a couple of years back and oversized most of the radiators. Much of the time, the boiler is running at ~50°C, and sometimes as low as 45°C (occasionally going up to 55°C), yet still heats the place at a reasonable rate. Downside to low flow temperatures is one needs to use 22mm or even 28mm pipe to allow for sufficient volume of water to flow. With a 7 bed property, you might need to go up to 32mm close to the boiler.

 

[richard1976]

We have been warned off a heat pump. The property came with an LPG tank which we were reliably informed was connected to a working boiler. We arrived to find it hasn't been connected in years, and the boiler is shot!! We are probably going to go with oil to the existing system (awaiting final quotes). Then upgrade radiators where required. I counted 27 radiators, but think i might have missed some, so changing it all isn't feasible at the moment!

When you do the heat loss calculations for radiator sizes, base the specifications on a heat pump even if you plan on using a gas or oil fired boiler. Bigger radiators means you can run at lower flow temperatures which will equate to better efficiency - I plumbed in a new heating system here a couple of years back and oversized most of the radiators. Much of the time, the boiler is running at ~50°C, and sometimes as low as 45°C (occasionally going up to 55°C), yet still heats the place at a reasonable rate. Downside to low flow temperatures is one needs to use 22mm or even 28mm pipe to allow for sufficient volume of water to flow. With a 7 bed property, you might need to go up to 32mm close to the boiler.

 

[montyjohn]

When you do the heat loss calculations for radiator sizes, base the specifications on a heat pump even if you plan on using a gas or oil fired boiler. Bigger radiators means you can run at lower flow temperatures which will equate to better efficiency - I plumbed in a new heating system here a couple of years back and oversized most of the radiators. Much of the time, the boiler is running at ~50°C, and sometimes as low as 45°C (occasionally going up to 55°C), yet still heats the place at a reasonable rate. Downside to low flow temperatures is one needs to use 22mm or even 28mm pipe to allow for sufficient volume of water to flow. With a 7 bed property, you might need to go up to 32mm close to the boiler.

I've done a lot of what you've said.

Fitted an oil boiler and new radiators going in to areas currently unheated, all sized for current heatloss. However, I'm anticipating heatloss to more than half, meaning I'll have massively oversized emitters suitable for ASHP.
I haven't upgraded the pipework, so primaries are still 22mm, however, where I've added pipework from the boiler to the old pipework, it all 28mm.

I think I can probably split the original primaries into two systems, rather then replace and double my flow capacity that way. Means a lot less new pipe.

Also, if I go down the underfloor heating route where I have solid floors, I'll be asking a lot less from the 22mm pipes, so my calcs suggest it should be ok.

It doesn't cost much more to future proof the system whilst you are at it.

Edit: Something I've read and don't know if it's true but below 40 degrees flow temps conventional boilers corrode internally a lot faster. So I've set this as a lower limit on my weather compensation controls.

 

[montyjohn]

27 radiators

Wow, must be a hell of a place.
I don't know how your heatloss calcs are looking, but if each radiator demands just 1500w (which is fairly small) you're looking at 40kW or more. Far too expensive to go down ASHP route as the upfront costs run away with themselves.
If you can get heatloss down to 14kW or less, ASHP really start to make sense.

 

[stuart45]

Do you know how the wall is constructed? E.g. Brick or stone?

 

[richard1976]

Do you know how the wall is constructed? E.g. Brick or stone?

Not sure. Seems to be stone/rubble