House extension - confused about mortgage implications

jp1181

We are having a single story extension on our house later this year, doubling the kitchen size, and adding a utility room and shower room. It does not require planning permission, but we are getting a permitted development certificate for the work.

We are not borrowing to do the work, we are able to finance it from a combination of savings and a generous gift from parents.

I am confused about the implications of this on our mortgage, and what opportunities there may to benefit from this in terms of what we pay for our mortgage, LTV, equity... Etc.

Please can someone explain whether we can remortgage to get a better rate, and/or can we remortgage based on the new value of the home with the extension. Or any other action we can take that would be beneficial.
Thanks

Archerychick

We added an extension to our house under permitted development.

Firstly don’t forget to let you house insurance know about the work, they will want to have the builders details along with their liability insurance in case anything goes wrong.

Once the work is complete get a valuation done, and see what the latest current valuation is and therefore if that changes your LTV ratio 

fergie_

You will probably need to let the lender know in advance as well - as ultimately you are doing something that materially affects their secured asset.

If all goes to plan, it can increase the value of the property, but that is only likely to matter come selling or remortgaging.

ACG

With the increased value you can potentially remortgage to a better rate. However with how rates have been recently that is probably unlikely unless you took out your mortgage in the last 12 months or so. 

jp1181

ACG said:

With the increased value you can potentially remortgage to a better rate. However with how rates have been recently that is probably unlikely unless you took out your mortgage in the last 12 months or so. 

We've moved 7months ago, we ported a number of previous mortgages as on decent rates (less than 3%) but did take a new mortgage for the rest which is at about 5.5%. 
Be interested to know if there is something we could do