If you are a shared owner and want to purchase more of your property, this is known as staircasing. By staircasing up you will own a greater proportion of your property and pay less rent. You can stair case upto 100% at which point you will become the owner of the property. You will need to refer to your current lease to find out when and how many times you can staircase up.
Your additional shares will be based on the full current market value of the property so you may need to carry out a valuation from NLM approved Valuers.
For further information please contact the NLM on 020 8815 4200