A home improvement loan is very easy to get these days and can come from a number of sources, you may also be able to get a finance deal on your conservatory from your supplier, but make sure that you read the small print on these deals to ensure that you are getting a good deal (0% for a fixed term deals often have a higher interest rate once the 0% part of the deal has run out).
Extending your mortgage is the first option to consider when financing your conservatory, especially if it is a larger conservatory. Some of the modern flexible mortgages will allow you to add this directly to your account immediately but for most mortgage extensions you will need to arrange this with your provider. As your mortgage is generally your cheapest form of borrowing this can often be the best option, but remember your mortgage is often over a long term and therefore you will be paying interest over a long period.
You can get a personal loan from many sources these days, specialist finance companies, banks and building societies just thre of your options. The advantage of a personal loan is that it is usually over a much shorter term than your mortgage, but the financial institutions make up for this by charging higher rates of interest.
A personal loan may be secured or unsecured, a secured loan requires a guarantee, usually on your property, whereas an unsecure loan doesn't.