Sofa Too Low? How to Raise the Seat Height with New Foam
A sofa too low to sit on comfortably is usually fixed with new seat cushion foam that is firmer, thicker or both, so you sit higher and sink less. Standard sofa seats sit about 43 to 48cm from the floor to the top of the cushion, and low lounge styles sit at about 38 to 43cm. GB Foam Direct cuts firmer replacement seat foam to your cushion sizes to bring a low or worn sofa back up.
Key takeaways
- Standard sofa seat height is about 43 to 48cm from the floor to the top of the cushion; low sofas sit at about 38 to 43cm.
- A sofa often feels too low because worn foam sinks under your weight, not because the frame is low.
- A firmer grade such as GB 41M Luxury Medium or GB 39H Luxury Hard sinks less, which raises the height you actually sit at.
- Dacron adds about 1cm of loft to each face of a cushion, but foam thickness is limited by the depth of the cover border.
- A piece of foam cut to the exact size of the seat, or a foam sheet, placed under the existing seat cushions raises the seat without needing new, deeper covers.
- GB Foam Direct has cut foam in High Wycombe since 1976, and orders before 11am Monday to Thursday are eligible for next working day delivery.
What Is a Normal Sofa Seat Height?
A normal sofa seat height is about 43 to 48cm, measured from the floor to the top of the seat cushion. Furniture retailers describe this range as keeping the knees and hips roughly level for most adults.
| Seat Style | Seat Height | How It Feels |
|---|---|---|
| Low or lounge sofa | About 38 to 43cm | Relaxed and sunken, but takes more effort to stand up |
| Standard sofa | About 43 to 48cm | Knees and hips roughly level for most adults |
| High seat sofa | Above about 48cm | Easier to get in and out of, and suits taller people |
These figures are taken at the top of an unloaded cushion. The height you actually sit at is lower, because the foam compresses under you, and that difference grows as foam wears.
Why Does My Sofa Feel Too Low?
A sofa usually feels too low because the seat foam has softened and now sinks further when you sit down. A cushion that measured 46cm when new can leave you several centimetres lower once the foam has lost its support.
The other common causes are a low lounge style frame, soft back cushion grades used in the seat, or fibre and feather fillings that flatten. Sagging springs or slack webbing under the cushions also drop the seat, and new foam will not fix those.
If your cushions dip in the middle or have flattened at the front edge, our guide to fixing sagging sofa cushions walks through the signs.
How Can You Raise the Seat Height of a Sofa?
You can raise the seat height of a sofa by fitting firmer foam, thicker foam, a Dacron wrap, a foam sheet under the cushions, or taller legs. Foam changes the cushion; legs change the frame, and the two can be combined.
Firmer foam is the change most people miss. A higher hardness rating means the cushion compresses less under the same weight, so you sit higher even when the foam is the same thickness as before.
Thicker foam adds height directly, but only up to the depth of the cover border. Beyond that, the cover either will not close or the seams strain, so a large increase needs new covers with a deeper border. Many people struggle to find a new, larger cushion cover that fits their sofa, which is why the next option is often simpler.
Placing a sheet of foam cut to size under the existing seat cushions raises the seat without touching the covers. Some of our customers do exactly this: the cushions go back on top as they are, and the extra layer lifts the whole seat. A higher seat can make it easier to stand back up after sitting down, which many people find helpful. We supply upholstery foam sheets for this. A standard sheet may not match your seat exactly, so if you would rather not cut one down yourself, order foam cut to size and we will cut it to the exact measurements of your seat platform.
Taller legs or furniture risers lift the whole sofa, including the arms and back. They suit sofas that are low by design, but they do not change how much the cushion sinks, so they work best alongside firmer foam.
Which Option Should You Choose for a Sofa That Is Too Low?
| Your Situation | Recommended Fix | Suggested Grade | Why |
|---|---|---|---|
| Old cushions that sink a lot | Replace the foam at the same thickness | GB 41M Luxury Medium | New, firmer foam stops the deep sink |
| Cushions up to 4 inches (10cm) thick | Replace with a hard grade | GB 39H Luxury Hard | Firm grade suited to thinner seat cushions |
| Heavy daily use or heavier users | Replace with the firmest seat grade | GB 39H Luxury Hard | High hardness for heavy use seating |
| Cover has a little spare room | Add Dacron and stockinette | Same grade plus Dacron | About 1cm of loft on each face |
| New, deeper covers are hard to find | Place foam cut to size under the cushions | GB 39H Luxury Hard | Lifts the seat and keeps your existing covers |
| Frame is low by design | Taller legs plus firmer foam | GB 41M | Raises the frame and stops the sink |
Our guide to what foam to use for sofa cushions explains each grade, and every seat grade above comes in our replacement sofa cushions range.
How Much Height Can New Foam Add?
New foam adds the extra thickness you fit plus the height you stop losing to compression. Work it out by measuring your sitting height on the old cushions, then deciding how many centimetres you want to gain.
For example, if you sit at 40cm and want 45cm, you need 5cm more height under load. Firmer foam at the same thickness recovers part of that, a Dacron wrap adds about 1cm a face, and anything more needs a thicker cushion and a deeper cover, or a foam sheet placed under the existing cushions.
Higher seats are not always more comfortable. If your feet no longer rest flat on the floor, the seat is too high for you, so raise it in steps rather than all at once.
How to Raise a Sofa That Is Too Low
To raise a sofa that is too low, measure the height you sit at, choose a firmer or thicker foam within the limits of your covers, add a foam sheet under the cushions if you need more, and re-measure once the new foam has settled.
Measure your seat height sitting down. Sit in your usual spot and ask someone to measure from the floor to the top of the cushion beside your leg, so you capture how far the seat sinks under your weight.
Decide how much height you want. Compare that figure with the 43 to 48cm standard range and note the number of centimetres you want to gain.
Measure the cover border. Measure the side border of each seat cushion cover from seam to seam, because this sets how much thicker the foam can be in the same cover.
Choose a firmer grade. Pick a grade that sinks less, such as GB 41M Luxury Medium for cushions 4 inches (10cm) and thicker or GB 42H Superior Hard for heavy use.
Add Dacron if the cover allows. Add Dacron for about 1cm of extra loft on each face, and stockinette so the fuller cushion slides into the cover.
Add foam cut to size under the cushions for big gains. If you need more height than the border allows, place a piece of foam cut to the exact size of the seat platform under the existing cushions, so you do not need new, deeper covers or to trim a sheet yourself.
Sit and re-measure. Use the new cushions for a week, then measure your sitting height again to check you have the height you wanted.
Our guide on how to measure foam cushions shows where to measure the border, and our Dacron and stockinette guide explains how the wrap changes the fit.
Mistakes to Avoid
- Measuring the empty cushion only. The unloaded height hides how far the seat sinks, so measure while you sit.
- Forcing thick foam into a thin cover. Oversized foam strains the seams and rounds the cushion into a dome, so put a foam sheet under the cushion instead.
- Choosing soft foam for the seat. Soft grades such as GB 33S are made for back cushions and will sink just like the old foam.
- Ignoring the springs. If the platform under the cushions dips, have it repaired before buying new foam.
- Raising the seat too far. A seat that leaves your feet off the floor is as uncomfortable as one that is too low.
Why Choose GB Foam Direct?
GB Foam Direct has converted foam in High Wycombe since 1976, starting with the furniture trade, and supplies one-off home orders as well as large manufacturers. Our upholstery grades are density tested to BS EN ISO 845, hardness tested to BS EN ISO 2439 and comply with the Furniture and Furnishings (Fire) (Safety) Regulations 1988. We work to ISO 9001 and give a 5 year guarantee against faults in manufacture.
Speak to Our Team
If you need help choosing foam to raise a sofa that is too low, call us on 01494 441177, email sales@gbfoam.com or fill out our contact form. We are in the office from 9am to 5pm Monday to Thursday and 9am to 3pm on Friday.
Sofa Too Low FAQs
What is the standard height of a sofa seat?
The standard height of a sofa seat is about 43 to 48cm, measured from the floor to the top of the seat cushion. Low lounge style sofas sit at about 38 to 43cm. The height you actually sit at is lower, because the cushion compresses under your weight.
How do I make my sofa higher to sit on?
Fit firmer seat foam so the cushion sinks less, add thicker foam up to the depth of the cover border, place a foam sheet under the cushions, or fit taller legs to raise the frame. Firmer foam is often enough on a sofa whose cushions have worn. For a large increase, a foam sheet under the cushions avoids the need for new, deeper covers.
Will firmer cushions make my sofa higher?
Yes, firmer cushions make a sofa sit higher because they compress less under your weight. The cushion may be the same thickness as before, but you stay further up in it. GB 41M Luxury Medium and GB 39H are medium to firm seat grades suited to this.
Can I put thicker foam in my existing sofa covers?
You can put slightly thicker foam in existing covers only if the cover border has some spare room. Dacron adds about 1cm of loft to each face without a big change in foam size. For more than that, either have covers made with a deeper border or place a sheet of foam cut to size under the existing cushions.
Can I put foam under my sofa cushions to raise them?
Yes, placing a sheet of foam cut to size under your existing sofa cushions is a simple way to raise the seat. It lifts the whole seat without needing new, larger cushion covers, which many people find hard to source. The foam should match the size of the seat platform so it sits flat and does not show. If you would rather not trim a standard sheet yourself, order the foam cut to the exact size you need.
Why is my sofa hard to get out of?
A sofa is usually hard to get out of because the seat is low or the foam sinks so far that your hips end up below your knees. Low lounge sofas at about 38 to 43cm are harder to stand up from by design. Firmer seat foam keeps you higher in the cushion and makes standing easier.
Are furniture risers a good way to raise a sofa?
Furniture risers raise the whole frame, including the arms and back, so they suit sofas that are low by design. They do not change how much the cushions sink. For a worn sofa, firmer foam usually makes more difference, and the two can be combined.
Is a higher sofa better for older people?
Many people find a higher, firmer seat easier to sit down on and stand up from, because the hips start higher. Comfort depends on your height, so check your feet still rest flat on the floor. For specific mobility needs, speak to an occupational therapist or your GP.
Cameron has emerged as a key marketing expert since joining GB Foam Ltd in 2017. A graduate of the University of Winchester, with a professional background in Public Relations; he has combined his content writing and brand awareness expertise with an in-depth knowledge of foam products and foam conversion technology to enhance the company’s marketing strategies and industry presence. Cameron has led numerous marketing campaigns, in both B2B and B2C segments, to further brand recognition and open up new business avenues worldwide.