diff --git a/crates/blockchain/src/metrics.rs b/crates/blockchain/src/metrics.rs
index 41b70bd7..81d00c29 100644
--- a/crates/blockchain/src/metrics.rs
+++ b/crates/blockchain/src/metrics.rs
@@ -460,12 +460,15 @@ static LEAN_BLOCK_BUILDING_PAYLOAD_AGGREGATION_TIME_SECONDS: std::sync::LazyLock
         .unwrap()
     });
 
+// Widened past the leanMetrics bucket set: block builds regularly exceed its top bound,
+// which collapsed every sample into `+Inf` and pinned the reported quantiles to that
+// bound. The range mirrors the phase timings this metric encloses.
 static LEAN_BLOCK_BUILDING_TIME_SECONDS: std::sync::LazyLock<Histogram> =
     std::sync::LazyLock::new(|| {
         register_histogram!(
             "lean_block_building_time_seconds",
             "Time taken to build a block",
-            vec![0.01, 0.025, 0.05, 0.1, 0.25, 0.5, 0.75, 1.0]
+            vec![0.1, 0.25, 0.5, 0.75, 1.0, 2.0, 4.0, 8.0]
         )
         .unwrap()
     });
diff --git a/docs/metrics.md b/docs/metrics.md
index 017dc9ea..10f274a3 100644
--- a/docs/metrics.md
+++ b/docs/metrics.md
@@ -36,7 +36,7 @@ The exposed metrics follow [the leanMetrics specification](https://github.com/le
 |--------|-------|-------|-------------------------|--------|---------|-----------|
 | `lean_block_aggregated_payloads` | Histogram | Number of `aggregated_payloads` in a block | On block production | | 1, 2, 4, 8, 16, 32, 64, 128 | ✅ |
 | `lean_block_building_payload_aggregation_time_seconds` | Histogram | Time taken to build `aggregated_payloads` during block building | On block production | | 0.1, 0.25, 0.5, 0.75, 1, 2, 3, 4 | ✅ |
-| `lean_block_building_time_seconds` | Histogram | Time taken to build a block | On block production | | 0.01, 0.025, 0.05, 0.1, 0.25, 0.5, 0.75, 1 | ✅ |
+| `lean_block_building_time_seconds` | Histogram | Time taken to build a block | On block production | | 0.1, 0.25, 0.5, 0.75, 1, 2, 4, 8 | ✅ |
 | `lean_block_building_success_total` | Counter | Successful block builds | On block production | | | ✅ |
 | `lean_block_building_failures_total` | Counter | Failed block builds (error building the block, signing the block root, or processing it locally) | On block production failure | | | ✅ |
 | `lean_block_proposal_attestation_build_phase_seconds` | Histogram | Phase-level time in block-proposal attestation selection | On block production | phase=select_payloads,compact,stf_simulate | 0.001, 0.005, 0.01, 0.025, 0.05, 0.1, 0.25, 0.5, 1, 2, 4, 8 | ✅ |
@@ -45,6 +45,12 @@ The exposed metrics follow [the leanMetrics specification](https://github.com/le
 | `lean_block_proposal_attestation_data_selected` | Histogram | Distinct `AttestationData` entries in the proposal block body | On block production | | 0, 1, 2, 4, 8, 16, 32 | ✅ |
 | `lean_block_proposal_aggregates_selected` | Histogram | Aggregated signature proofs in the proposal result after compaction | On block production | | 0, 1, 2, 4, 8, 16, 32, 64, 128 | ✅ |
 
+> `lean_block_building_time_seconds` intentionally deviates from the leanMetrics bucket
+> set, which tops out at 1s. Real builds on our devnets routinely run past that, so every
+> sample landed in `+Inf` and `histogram_quantile` reported a flat 1s ceiling. The range
+> now covers the same span as the `lean_block_proposal_attestation_build_phase_seconds`
+> phases it contains.
+
 ## Fork-Choice Metrics
 
 | Name   | Type  | Usage | Sample collection event | Labels | Buckets | Supported |