Hi OP
please read the attached link from citizens advice www.citizensadvice.org.uk/housing/repairs-in-rented-housing/repairs-common-problems/repairs-infestations-of-pests-and-vermin/
im assuiming you have an Assured Shorthand Tenancy.
can I also suggest the following for you:
if you can keep a diary of the noise and time of the rats/ mice and photo graphic evidence.
keep a record of the names and times of everyone you have had contact with.
contact the councils environmental health officer if you have not already and ask for their advice and ask for some traps (humane or otherwise)
I would not suggest the papers- to be honest this is all too common a problem- as councils and housing associations are so understaffed and under budget.
the best way to deal with a housing association is to bypass the customer services team and go straight to the Head of Customer Services and cc in the chief exec and chair of the board. You should find their details on google/ their website. be polite, but stress the urgency and how much dispart this is causing you and your children. In your email to them state you have contacted citizens advice and your next step will be to contact the housing ombudsman if not sorted ( [email protected]).
please make sure holes in the walls are not filled with foam- it must be something that sets hard or the rats can eat through it, or you will have the same problem.
I have never heard of having to take out the boiler and water tank though, they should be able to fix holes around with metal mesh and cement, all pipework makes holes so this is not uncommon.
one thing I would say- and I'm not saying that is the case here- is you need to be sure that nothing you or your family (or your neighbours) are doing is attracting the rats or bugs.
bugs once pest control have been should be completely clear, so they maybe still on any furniture, pets or clothes/ fabrics that have not been treated- ie if you moved stuff outside. fabrics need a 60^ + wash to kill bugs. your landlord will not be responsible for your furniture or clothes- etc which I know is not right, but that's the law. I also know the if you don't clear everything then they re always going to come back.
the rats and mice, they will eat anything and will probably be coming in for a warm. but there must be some food source for them either in yours or your neghbours for them to keep coming back, either in the form of food, rubbish or crumbs.. potentially there maybe a nest outside as well, which is why they come back so quick. can you see/ do you know if your neighbour is clearing away all their stuff- if not, you can fix the holes, but unless its 100% airtight then they will come back.
if afraid that your landlord maybe responsible for getting rid of the bugs and rats, but they are not responsible for the cleaning afterwards- that's any good will you have and how nice they want to be to you. which is why I say be polite but firm in emails- this has a better outcome.
good luck