Solid Wall Insulation

[bottler]

Folks.

I have an old Town House : -/+ 1850's. Plastered walls. No form of insulation. No ventilation. I'm not sure if the walls are Cementitious or Lime Mortar (need to check). I will need to insulate internally as externally is not an option.



Here are my questions:

Q1 - DRY-LINING INSULATION: I'm hearing conflicting reports. That Dry-ling / Internal wall insulation (IWI) is not suitable for older homes as the Dew Point will typically be on the inside of the cold wall behind the insulation?

The house was bone dry up until i stopped the dehumidifiers 1.5/ 2 years ago. So maybe i just need to re-plaster with the right plaster mix? I've been told to avoid gypsum plaster as it's very damp prone. What plaster/ materials should be used? Lime Plaster is it?

But for heat retention, are there any advised insulation/ tips/ tricks?

Q2 - ATTIC CEILING INSULATION: Insulating the area between the attic ceiling and the roof tiles needs special consideration i believe? As there needs to be sufficient airflow for the joists to remain dry? Any advice on how to approach the insulating?

Q3 - VENTILATION: Guessing i need to burrow holes and to add a RH sensitive ventilation system? Will this suffice?

Q4 - CENTRAL HEATING: the right system will of course be crucial going forward. There's no gas in the town. Oil isn't an option as there's no back garden. I'm hearing good reports on Heat Pump Systems. However they are 3 times the initial cost outlay of Solid Fuel Burners. Are Heat Pump Systems worth the outlay over say a Log Burner System?



And a few images of the Attic... to see what I'm dealing with...

Thanks in advance for any input, no matter how small.

 

[endecotp]

That Dry-ling / Internal wall insulation (IWI) is not suitable for older homes as the Dew Point will typically be on the inside of the cold wall behind the insulation?

There are various factors to consider, such as whether the construction includes a vapour barrier or not, and whether the insulation material absorbs and releases moisture or not. Also whether the wall is subject to driving rain.

I've found the case studies produced by Historic Scotland useful: https://www.historicenvironment.scot/about-us/what-we-do/conservation/refurbishment-case-studies/ . Case study 4 woild be a good place to start; it compares various insulation products and in section 6 studies the effect on moisture in the wall. They conclude that none of the products tested is damaging to the wall.