Discount Mortgages Explained

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    “We know that time is precious for you, we can work around your availability while searching for the most competitive mortgage products and overseeing your mortgage application from start to finish”.

    Jonathan Smith – (CeMAP, BA Hons, Aff SWW, CeRER)

    When you’re looking to build your own home, you’ll more than likely need a self-build mortgage to fund your project. Before the home building process begins, you need to know exactly how much you can borrow to help you design, plan and budget accordingly. As every self-build project is different, however, you may be wondering how this mortgage will be calculated. This is when a self-build mortgage calculator is a helpful tool as it gives you an idea of what you can borrow.

    At Trinity Finance, our mortgage brokers can discuss your self-build project in depth and compare the deals from different lenders. They can give you an accurate assessment of your affordability for a self-build mortgage. This will include how much you can borrow and the repayments you’ll need to make. But if you simply want to get an idea of how much you can borrow before speaking with a broker, you can use our self build mortgage affordability calculator.

    What is a self-build mortgage?

    A self-build mortgage covers the costs of building your home. This can also include the cost of buying the plot of land to build it on. You can also use a self-build mortgage to fund extensive conversion or renovation works on your existing home. The funds are paid either in advance or arrears and are provided in stages as your project progresses. This is what makes a self-build mortgage different from a standard residential mortgage, for which you receive the funds in a lump sum to enable you to buy a property. As such, self-build mortgages are more complex to arrange, not least because each project is completely different from any other.

    How is a self-build mortgage calculated?

    To calculate how much you can borrow for a self-build mortgage, a lender takes different factors into account. These include how much you want to borrow, the amount of deposit you can pay, your preferred mortgage term and your preferred interest rate. You also need to decide between an interest-only and a repayment mortgage. Self-build mortgage lenders also look at other factors, such as your affordability, your credit history and your status. For example, whether you’re a first-time buyer, looking to move home or remortgaging.

    Why use a self-build mortgage calculator?

    You may just be thinking about building a home at this point and be curious as to how much you can borrow. Or you may be at the early design and planning stages of your self-build project and just want to get a rough idea of how much you can borrow when you’re ready. That’s exactly what a self-build mortgage calculator is for. Using the basic information you input, it provides you with an indication of the amount you can borrow and what your repayments will be.

    Can a self build mortgage calculator confirm how much you can borrow?

    No, a self build mortgage calculator is for illustrative purposes only. As mentioned earlier, self-build mortgages are complex, with all manner of information having to be taken into account. A self build mortgage calculator is a convenient tool that takes the basic information you provide and gives you a guide on how much you can borrow. As well as the amount you can borrow, it estimates the loan-to-value (LTV) ratio you can expect and approximately how much your repayments will cost. You can compare how these will change if you choose a different mortgage term or interest rate.

    Self-build project costs to consider

    Before using our self build mortgage UK calculator, think about all of the costs involved with your project. This will give you a better idea of what to enter for your property price. Consider the following:

    • The approximate cost of the plot of land needed to build your home on
    • The anticipated size of your new home
    • The types of materials you’re going to build your home with
    • What internal decoration and features you want to include
    • The external landscaping that will be required

    How accurate is a self-build mortgage calculator?

    Mortgage lenders and brokers use self-build mortgage calculators to give an indication of the amount that you can borrow. You can also use our online self-build mortgage calculator for the same purpose. However, as self-build mortgages are complex, the results provided by a self-build mortgage calculator are not definitive. Lenders all have their own criteria when deciding how much to lend borrowers.

    For example, it can depend on your age, your affordability of the mortgage, your credit history, how much deposit you have, how much you want to borrow and over what term, your experience when it comes to building property and the type of property that you wish to build. With so many factors to take into account, this type of mortgage is assessed on a case-by-case basis.

    We recommend using our self-build mortgage calculator to give you a guide on how much you can borrow and an estimation of your repayments. Then, when you’re ready to proceed with a self-build mortgage, our mortgage brokers will discuss your project and circumstances in detail with you. They’ll compare different lenders’ self build mortgage deals, checking that you meet the eligibility criteria, and present you with the rates and terms for each. This will allow you to check not only the best deals financially but also those offering the most flexibility for your needs.

    To speak with one of our self-build mortgage specialists, just give us a call on 01322 907 000. If you prefer, send an email to us at or an enquiry via our contact form. We will reply to you as quickly as possible with more information.

    How to use our self build mortgage UK calculator

    Our easy-to-use mortgage calculator is a great way to get an idea of how much you can borrow and what your repayments will be. Bear in mind that every lender has its own criteria so the actual figures for your self-build mortgage will be different.

    Select your status and choose your repayment type

    Select your status from the options available, such as whether you’re a first-time buyer, looking to move home or remortgaging. Then choose between a repayment and an interest-only mortgage.

    Enter the property value and deposit amount

    Consider as many of the self-build project costs involved as you can when entering the property value, as detailed earlier. For the deposit amount you can pay, be sure to allow for the fees payable when building your own home. Otherwise, when it comes to applying for your self-build mortgage, your deposit may not be as high as you thought it would be. Taking these costs and fees into account before entering the property value and deposit will give you a more accurate result when using our self build mortgage UK calculator to determine how much you can borrow.

    Enter your preferred repayment terms

    Next, enter the length of the mortgage term you prefer. This is the period you wish to repay your mortgage over. Then, enter your preferred interest rate. An approximate amount for your monthly repayments will be calculated.

    Get expert advice from a self-build mortgage broker

    Building your dream home is an exciting prospect and a self-build mortgage can help you to turn it into a reality. Our self-build mortgage calculator can give you an idea of the amount you can borrow and how much your repayments will be before getting an accurate assessment from our mortgage brokers. Located throughout Kent, London and Edinburgh, our brokers are well versed in self-build mortgages. This niche type of mortgage is complex to arrange and our brokers take the time to discuss your self-build project in detail before preparing your application.

    Your dedicated mortgage broker will ensure that you have all of the necessary documentation prepared to avoid any delays in the mortgage process. They will also advise you on any schemes that offer financial support for self-build projects, such as Help to Build. As well as that, they will ensure that you are aware of the fees payable for your self-build project. For example, planning application fees, building regulation fees, survey fees, legal costs, your lender’s fees, the architect’s fees and insurance costs. That way, there won’t be any nasty surprises when it comes to budgeting for your project.

    Flexibility in your self-build mortgage deal

    At Trinity Finance, we have access to the entire market. This enables our mortgage brokers to search for and compare all suitable self-build mortgage deals. We have access to exclusive broker-only deals that you wouldn’t otherwise be offered if you went direct to a lender. Our mortgage brokers can find deals that offer the flexibility you need and negotiate for better deals on your behalf.

    For example, you may be able to take advantage of an interest-only option while the construction works are in process. Or you may be able to switch to a lower interest rate once your property reaches a habitable condition. Some lenders may reward you with a discount in the interest rate for making your newly built home energy efficient. And some lenders allow you to make overpayments without being penalised. Our mortgage experts also deal with specialist lenders to ensure that any potential obstacles can be dealt with. You may want to build a home with a non-standard construction, for example, or are self-employed with an irregular income.

    Get in touch with an expert to get your self-build project underway

    To get professional advice on the financial aspect of your project and start your self-build mortgage application, give us a call on 01322 907 000. Alternatively, send your details to us by email at or via our contact form. One of our mortgage advisers will reply to you as quickly as possible to discuss your self-build project plans and mortgage needs in more detail.


    Yes, although not as many options will be available to you as there would if you bought a new-build home or an older existing property. This is because self-build mortgages pose a higher level of risk for lenders. Our mortgage brokers know which lenders to approach for a first-time buyer self-build mortgage and will negotiate for the best deal on your behalf.

    As well as using the services of a lender, mortgage broker and solicitor for your self-build mortgage, there are various other professionals whose services you may wish to use. These can include an architect, a site manager, a planning consultant, a surveyor and a team of builders. It really depends on how involved you plan to be with your self-build project.

    Lenders typically offer self-build mortgages with a 75% loan-to-value (LTV) ratio. This means that you’ll need to pay a deposit that equates to 25% of the building project’s value. Each lender has its own criteria, however, and some will request a higher deposit amount while others will consider a lower amount. For example, if you already own the plot of land you wish to build your home on, they may lend based on the land’s value.

    Yes, some lenders offer self-build mortgages with a 100% LTV. To be eligible, you will need to provide security for the lender. This is usually in the form of the plot of land you wish to build on, which you should already own outright.