Granny Annexe Calculators
Compare annexe costs against care home fees, estimate the effect on your property value, and see typical monthly running costs.
Care Cost Savings Calculator
Compare annexe vs care home costs
Your Situation
UK care home costs average £1,300-£1,500 per week (source: Lottie.org 2026). South East England costs are typically higher. Costs vary by region and level of care.
Care Home Cost
£338,000
£1,300/week × 5 years
Grannexe One-Time Cost
£110,000
Average one-bedroom annexe, all inclusive
Your Potential Savings
£228,000
Plus your family stays together
Cost Comparison
Property Value Calculator
Estimate your property value increase
Property Details
Annexe Investment
£110,000
Estimated Property Value Increase
+£22,000
~20% of annexe cost adds to property value
Net Investment Cost
£88,000
New estimated property value: £522,000
Property value increases vary based on location, annexe quality, and market conditions. 20% is a conservative estimate based on industry research.
Monthly Running Costs
Typical annexe running costs vs care home
Grannexe Monthly Costs
Electricity
Energy-efficient heating & appliances
£60-£80
Water
Connected to mains supply
£20-£30
Council Tax
Ancillary accommodation (no separate charge)
£0
Insurance
Contents & structure
£15-£25
Total Monthly Cost
£95-£135
Care Home Monthly Cost
£5,633+
Average UK care home (residential)
Monthly Saving
£5,498+
Per month compared to care home fees
Annual saving: £65,976+
Why no Council Tax? When used as ancillary accommodation by a family member, granny annexes typically don't attract a separate Council Tax charge. The annexe is considered part of the main dwelling.
Finance Calculator
Estimate your monthly payments
Payment Options
Estimated Monthly Payment
£917/month
Over 10 years (120 months)
Ways to Pay
- Equity release from your property
- Remortgage options
- Family contribution schemes
- Savings or inheritance
Representative example only. This is a simplified illustration. Actual rates and terms will vary based on your circumstances. We can discuss finance options during your free consultation.
Want an Accurate Quote?
Book a free site visit and we'll give you a detailed quote based on your actual requirements. No obligation.
Speak to our team
01689 818400