Clay Court Manual for Konglungen Tennis
Spring, Summer and Fall: Achieving consistent bounce, controlled slide and minimal maintenance
A clay court is an integrated system
Consisting of geometry, proper materials, moisture and routines. If one of these components fails, the rest becomes merely superficial.
🎾 Even Playing Surface
With predictable bounce throughout the season
👟 Controlled Slide
Neither like a sandy beach nor slippery concrete
🔧 Fewer Repairs
Minimal dust and fewer emergency fixes
📅 Good All Season
A court that stays excellent through September, not just May
Spring Start
Week-by-week guide from winter to playable court
Summer Maintenance
Daily, weekly and monthly operations that work
Fall Closing
Winter preparation – crucial for next spring
1. Court Profile at Konglungen
The thickness of the clay layer is a deliberate choice that affects the court's character and maintenance.
Konglungen: Approx. 40–45 mm active clay layer
Characteristics:
- Faster court with cleaner bounce
- Less plowing and clay migration
- Inspired by Swedish style (Båstad)
- Adapted to Norwegian climate
Requirements:
- Requires precise watering and routines
- Less forgiving of sloppy work
- Provides a "sweet spot" for Norwegian conditions
2. Materials: Function over Name
Suppliers use different terminology, so we focus on function to avoid confusion. Materials are typically crushed brick.
A) Structure/Leveling Material - typically 0–3 mm ("Top Dressing")
This is the court's "backbone" – not for weekly spreading.
Use:
- For frost heave, depressions, settlements
- Leveling and stabilization
- Spot repairs that must be compacted
B) Surface/Seasonal Material - typically 0–2 mm ("Båstad Clay")
This is the red, active playing layer.
Use:
- Thin applications throughout the season
- Seal the surface and protect the structure layer
- Better ball marks and improved slide
- See coarse structure/base? → Too little 0–2 mm
- Court becoming dark, dense and slippery? → Too much 0–2 mm or over-compaction
Quantities per Court per Season – Theory vs. Practice (Adjusted Based on Norwegian Experience)
Theoretical (even 5 mm layer over the entire court 18 × 36 m):
approx. 3.24 m³ ≈ 5 tons (at typical density of 1.5–1.6 tons/m³).
Practical annual maintenance (normal Norwegian clay court, established surface):
Total new material per season: 1–3 tons (often closer to 1–2 tons).
- Spring (main top-up): approx. 0.5–1 ton (often 500 kg as refill)
- Summer/autumn (as needed): 0.5–1 ton extra if there is significant wear, wind loss, or depressions
Quantities vary greatly from court to court – depending on:
- Climate (wind, rain, frost heave)
- Usage (number of playing hours/players)
- Drainage and geometry
- Whether the court is loose or firmly packed
- Preferably use the same type of material (e.g. only 0–2 mm) if possible – combining 0–3 mm + 0–2 mm does not always bind well to the base.
- Typical thickness of the active layer: 3–5 cm total.
- Observe the court: If it looks too coarse/rough → add more topping. If it becomes dark/dense/slippery → use less or improve rolling/watering.
3. Line Management: Seasonal Practice
Proper line management extends the lifespan of your lines and protects the court surface during winter months.
Standard Practice at Konglungen
Our routine follows a seasonal cycle that balances line preservation with optimal court preparation:
🍂 Autumn (September-October)
Remove all lines before winter
- Prevents lines from being damaged by frost heave
- Allows unrestricted surface work in spring
- Protects line material from winter deterioration
❄️ Winter (November-March)
Lines stored away
- Court surface can settle naturally
- Spring preparation work is not hindered
- Lines remain in good condition
🌱 Spring (April-May)
Reinstall lines after new clay application
- Complete all structural repairs first
- Apply and roll new surface material
- Install lines on prepared, stable surface
- Secure properly with stakes and water
Why This Practice Works
- Better spring preparation: Unrestricted access to entire surface for leveling and clay application
- Line longevity: Lines last longer when protected from winter freeze-thaw cycles
- Surface quality: New clay can be applied and rolled evenly without working around lines
- Proper installation: Lines go onto a prepared, stable surface rather than uneven winter-worn clay
Alternative Practice: Year-Round Lines
Some clubs choose to leave lines in place year-round. This practice:
Advantages
- Less spring installation work
- Lines ready immediately when season starts
- Simpler routine for volunteers
Disadvantages
- Lines may deteriorate faster from winter exposure
- Spring work must navigate around fixed lines
- New clay application is more complicated
- Lines may become embedded or uneven
- Higher risk of frost damage to line material
Modern Court Systems
Newer hybrid court surfaces (TopClay, PlayClay) use permanently glued lines that eliminate seasonal removal:
- Lines are glued permanently to the surface
- No seasonal removal or installation needed
- Court playable year-round (when snow-free)
- Different maintenance approach than traditional clay
Spring Line Installation Tips
When reinstalling lines in spring, follow this sequence:
- Complete all surface work first: Structural repairs, clay application, and rolling must be finished
- Mark line positions accurately: Use measuring tape and string to ensure proper court dimensions
- Lay lines on dry surface: Wait for a dry day with minimal wind
- Secure with stakes: Use proper line stakes at recommended intervals
- Water and settle: Light watering helps lines settle into the clay surface
- Check and adjust: Verify all lines are straight and properly tensioned
4. Delivery and Storage of Clay Court Material
The choice of delivery method affects not only cost, but also logistics, maintenance workload, player experience, and long-term court quality.
Why Clay Courts Require Regular Material Replacement
Clay courts continuously lose surface material due to play, weather, and maintenance activities. Over time, the upper layer gradually wears away, which may result in:
- Hard and slippery court surfaces
- Surface cracking
- Increased dust formation
- Reduced ball bounce and sliding quality
Annual top-dressing is therefore essential to preserve playing performance, safety, and the overall lifespan of the court. Regular material replacement also reduces the risk of larger and more expensive rehabilitation work later.
Delivery Options
Tennis clubs typically choose between two delivery methods:
📦 Big Bags (Bulk Delivery)
Approx. 1 ton per bag
Advantages:
- Lower total cost per ton
- Efficient logistics (crane/lifting)
- Reduced manual labor
- More consistent material quality
- Environmental benefits (less plastic waste)
Disadvantages:
- Requires lifting equipment or crane delivery
- Requires dedicated storage space
- Requires more detailed planning of deliveries
📦 Small Bags
25 kg bags on pallets
Advantages:
- High flexibility
- Easy storage of small quantities
- Gradual refilling during season
- Manual distribution without machinery
- Low initial investment
Disadvantages:
- Higher material cost per ton
- Significantly more manual labor
- Increased plastic waste
- More volunteer work required
Total Cost Considerations
Material cost alone does not determine the most economical solution. When transport, labor, and maintenance efficiency are included, the overall cost picture often becomes:
| Delivery Method | Material Cost | Labor Requirement | Total Operational Cost |
|---|---|---|---|
| Big Bags | Lower | Lower | Usually lowest |
| Small Bags | Higher | Higher | Usually higher |
Norwegian Clay Court Realities
Clay court maintenance in Norway presents unique challenges that influence material strategy:
Short Playing Season
Most Norwegian outdoor clay courts operate approximately from April to October. This creates:
- Limited time to rebuild and stabilize the playing surface
- Gradual surface deterioration if maintenance is minimized
Climate and Wind Exposure
Wind and dry weather conditions increase:
- Dust formation
- Surface drying
- Material loss from the top layer
Volunteer-Based Maintenance
Many clubs rely heavily on volunteer work, making time-efficient solutions more valuable. Maintenance strategies that reduce workload often improve long-term sustainability.
Recommended Solutions
Bulk delivery or big bags are usually the most efficient and cost-effective solution.
Small bags can be useful as a supplementary solution when only limited quantities are required.
Storage of Clay Court Material
Proper storage is essential for maintaining material quality and protecting financial investment.
Clay material should be stored:
- In dry conditions
- On a stable and drained surface
- Protected from rain and groundwater
- Easily accessible for distribution
Quick Decision Guide: What's Right for Your Club?
✅ Recommended for Clubs with 2+ Courts: Big Bags
Based on Konglungen's experience, Big Bags (approx. 1 ton per bag) offer the best combination of cost-efficiency and reduced workload – crucial for clubs relying on volunteer work.
Calculate Your Needs
Estimate 1–2 tons per court per season
- Spring main top-up: 0.5–1 ton
- Summer/fall as needed: 0.5–1 ton
Contact Suppliers
Request quotes and logistics support
- Price per ton for Big Bag delivery
- Transport costs
- Mobile crane assistance for unloading
- Delivery schedule flexibility
Prepare Storage
Essential for protecting your investment
- Dry, covered location
- Stable, well-drained surface
- Easy access for distribution
- Protection from rain and groundwater
Why Big Bags Work for Small Clubs
Lower material cost + significantly reduced labor = lowest total operational cost
Crane delivery places entire season's supply in one go – no multiple handling rounds
More consistent material from single batch + minimal plastic waste
Small bags (25 kg) make sense as a supplementary solution for mid-season spot repairs or if you need only 200-500 kg total. For regular annual maintenance of 2+ courts, Big Bags remain the smarter choice.
5. Technical Rule: Slope and Drainage Geometry
A good clay court is not flat like a living room floor – it must have controlled slope to handle water. The court should slope in one single plane (true plane) for even runoff and the best playing experience.
Recommended slopes (unidirectional / in one direction):
- Side to side (from one sideline to the other sideline): Preferred direction – gives least impact on play and best visibility of the lines.
- End to end (from one baseline to the other baseline): Good alternative if the terrain dictates it – accepted in most standards (e.g. ITF/ASBA), but somewhat more noticeable to players than side-to-side.
- Slope: Typically 0.25–0.35 % for clay courts (approx. 1 cm per 3–4 meters) – gentler than for hard courts (0.83–1 %).
Why unidirectional slope is better – especially for children:
With slope in one direction (side-to-side or end-to-end) the white lines appear straight and consistent from both sides of the court. This is easier to judge, especially for children and younger players who have less experience with perspective.
Avoid cross-slope from center outward to the sides ("crown" or ridge in the middle) – the court becomes highest along the centerline and slopes down toward both sidelines. This can create optical distortion: lines appear curved or uneven when looking across the court, making it harder to judge "in/out" correctly – particularly challenging for children.
Avoid:
- Bowl shape – water collects in the middle or low points
- "Tent shape" / crown – high center, unpredictable ball path and poorer line visibility
- Slope toward or away from the net / centerline – creates unfair advantage and poor drainage
Place a straight board / straightedge (3–4 m) across the court. You should see a faint light strip at the outer edges – even slope without a clear bulge in the middle or zero gap.
6. Spring: From Winter to Playable Court
Spring work sets the standard for the entire season. Mistakes here become expensive to fix later.
Phase 1: Inspection and Preparation (early spring, March–mid-April)
Do:
- Remove leaves, twigs, and all organic material
- Mark settlements, frost heave and poor drainage zones
- Light rolling to "read" the court's condition
Don't:
- Apply much new clay in cold/windy periods
- Hard brushing on dry court
Phase 2: Structural Work and Geometry (April)
This is by far the most important phase.
- Fill depressions/settlements with 0–3 mm (max 10–15 mm per layer)
- Water lightly (moist, not soaked)
- Roll well
- Repeat until evenness and slope are correct
Goal:
- Correct cross-slope 0.5–1%
- Even load-bearing capacity without soft/"floating" zones
Phase 3: Surface Application (late April–May)
April is often cold and windy – new dry clay + wind = dust and clay migration.
- Use April for structure and leveling
- Apply main quantity of 0–2 mm late April or May (when night temp > +8°C and wind calm)
- Divide into 2–3 thin applications: Spread evenly → Water thoroughly → Roll lightly → Let dry before next round
Result:
- Minimal dust
- Better binding
- More durable surface all summer
7. Summer: Daily and Weekly Maintenance
Good summer maintenance is about little and often – not big emergency fixes.
Daily/after play (players' responsibility, 2 minutes):
- Close holes with your foot
- Brush in circles (start outside, work toward center)
- Extra round in high-wear zones (behind baselines, service boxes)
Weekly (court team):
- Light rolling as needed
- Check lines, joints and fasteners
- Small spot applications (0–2 mm) where surface opens up
- Adjust watering: Little and often beats seldom and much
➜ Read complete summer maintenance guide with monthly routines
8. Fall: Closing that Sets the Standard for Next Spring
Avoid "giving up" toward the end – it directly affects spring.
- Even out wear and fill holes thoroughly
- Final roll for even compaction
- Ensure good drainage – water must run off